SOME OBSERVATIONS ON THE NERVOUS SYSTEM OF A BUTTERFLY

DISSERTATION SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS

FOR THE AWARD OF THE DEGREE OF

jlagter of ^^ilogopfip IN

ZOOLOGY IN THE FACULTY OF LIFE SCIENCES

THE ALIGARH MUSLIM UNIVERSITY, ALIGARH

BY

MASOOM ZEHRA

DEPARTIVIENT OF ZOOLOGY ALIGARH MUSLIM UNIVERSITY

ALIGARH (INDIA)

1 9 8 9

\s >\.f

,r^

O'

ALIGARH MUSLIM UNIVERSITY

Humayun Murad Ph. D

HEADER

D E P A R T M E N T OF Z O O L O G Y

ALIGARH - 202 002, INDIA

May 21, 1990

This i s to c e r t i f y tha t the d i s s e r t a t i o n

for MoPhil. degree in Zoology of the Aligarh Muslim

Univers i ty , Aligaxh has been completed by Miss Masoom

Zehra, under ray supejrvisiono I t i s o r ig ina l in nature

and I have permit ted the candidate to submit i t fcr

the award of M.Phil, degree in p a r t i a l fulf i lment of

the MoPhilo requirements in Zoology,

( Humayun^ Murad ) Suriervisor

ACKNOWLEDGEMENTS

The author wishes to express her most sincere appre­

ciation to Dr, Humayun Murad for his precious guidance, contin­

uous encouragement, critical and constructive suggestions

during the progress of research without which this work would

never have come to light. I am deeply indebted to him indeed.

I feel highly obliged to Prof. Mumtaz A. Khan,

Chairman, Department of Zoology for providing necessary

laboratory facilities,

I am very much thankful to Kr, Ammar Ahmad Khan for hel

ing me financially during the course of my studies.

It is my pleasant duty to acknowledge the assistance

of my lab. colleagues Dr. Muzaffar Atiqui, Dr. (Miss) Archana

Bansal, Miss Robina Naseer and Mr. Mohd, Amir, whose help

proved to be very useful during this research work .

I have no words to express fully the indebtedness,

benevolance and gratitude I owe to my parents.

\ % ^

MASOOM 2EHRA

C O N T E N T S

Page No«

INTRODUCTION 1 - 8

REVIEW OF LITERATURE 9 -15

MATERIAL AND METHODS 16 -17

RESULTS AND DISCUSSION 18 -27

REFERENCES 28 -44

•k-kieitleiiititit

INTRODUCTION

The Monarch butterfly Danaus chirvslppus (L) belongs

to the order Lepidoptera and family Nymphalldae which is a

dominant family among lepidopterans. The characters of this

family are; forelegs in both sexes are reduced in size usually

folded under the thorax and functionally impotent, the tibiae

are short and clothed with long hairs hence the name "brush

footed butterflies" Imms (1957)» It is usually seen during the

months of May and June, They are found in India, New Zealand

and Australia. It feeds on milkweed Asclepias curassavica but

but had now been observed feeding on Gossvpium arborium

(musturd). These Lepidopterans are one of the most familiar

and easily recognizable among insects and in this order

coloration has reached the highest degree of specialization.

These insects have always been popular objects to study.

Economically, Lepidopterans are of great importance in their

larval stages, as they bear cutting type of mouthparts.

Majority of injurious species devour the foliage and shoots

of trees and crops; a smaller number bore into stem or attack

underground parts. Several species are injurious to timber,

others attack manufactured goods as carpets, clothings and like

wise, some are extremely destructive to stored grains. Some of

these insects create great trouble to agriculturists and

farmers.

-2-

According to Roonwal (193 6, 193 7) the central nervous

system originated as a thickening of the ectoderm on either

sides of the mldventral line. At about the time of segmentation

and prior to the dorsal closure of the blastoderm to form an

embryo rows and columns of large neuroblasts arises from beneath

the superficial cells of the ventral epidermis.

Considerable work has been done on the nervous system

among different insect groups as Hymenoptera, Diptera and

Coleoptera but little work has been done about the nervous

system of lepidopterous insects. The present study is concerned

with the Central Nervous System of a Monarch butterfly D^naus

chrvsippus (L.). A generalized picture of the lepidopteran

nervous system was given by Colhoun (1935), Treherne (1966)

and House (1977). Chauthani and Callahan (1967), Kuwana (1932)

described the nervous system of silkworm Bombvx mori. In 1961

Ehrlich and Davidson successfully studied the internal anatomy

of Danaus Plexippus (L) (Nymphalidae).

The nervous system of a butterfly is divided into three

divisions, the Central nervous system, the Peripheral nervous

system and the Sympathetic nervous system. The Central nervous

system is a conducting system ensuring rapid functioning and

coordination of effectors, modifying their responses according

to the input of peripheral sense organs, Snodgrass (193 5) studied

the evolution of the annelid - arthropod nervous system from

-3-

whlch It is very clear that the first central group of nerve

cells had its origin in the ectodeirtn at the anterior pole of

the body forming a small ganglion associated with a sensory

apical plate. Later there appeared several groups of paired

sensory cells at the bases of tentacular or other sensory organs

behind the apical plate. The central neuroendocrine system of

insects control many aspects of physiology and behaviour,

Raabe (1982), Truman and Taghert (1983) studied the

endocrine organs in detail. Cell and tissue culture have made

a major contribution to our understanding of biochemistry,

physiology and morphology of invertebrate nervous system.

Nervous system basically consists of brain which is principal

association centre of the body receiving sensory input from the

sense organs of head and via ascending intemuncial fibers from

the most posterior ganglia. The brain of most lepidopterans

species has been studied in a generalized pattern by

Bretschneider (1921), (1924 a,b), Hanstrom (1925), Schrader

(1938), and Ehnbom (1948), Others like Kenyon (1896),

Bretschneider (1913), Hanstrom (1928), Porer (1943), Bullock

and Horridge (1965) gave description of adult lepidopterans

brain microanatomy. Brain, as it is the computer or the master

organ of the body regulates different vital functions as growth,

reproduction metamorphosis etc. Our present understanding of

the function of the nervous system provides an excellent example

of the cumulative values of the complementary approaches to a

-4-

single problem, ultimately the function of nervous system

becomes the province of the behaviourist concerned with the

Ways in which the animal responds to the environment. The

Central nervous system of Danaus involves a marked expansion

of the brain and outward rotation of the protocerebral lobe

and a fusion of sub-oesophageal ganglion with a ventral tri-

tocerebrum. The attention of insect neurophysiologists is no>

being focussed on the central nervous system morphology and

pharmacology with special reference to generation of behaviour.

The primitive brain lies above the anterior end of oesophagus.

Brain structure and behaviour was studied by House (1977)

Smith (1962) pointed out that a shortage of time and patience

on the part of the morphologist is the chief reason for the

lag in providing an account of the insect nervous system. Th-:̂

available literature reveals that majority of the researchers

on this very particular subject, especially in Lepidoptera

have confined themselves to the larval forms as they are

destructive in this very stage. Du Pbrte (l9l5), Swaine (1920),

Hillemann (1933), Bickley (1942), Likky (1959), Srivastava

(1959), Mathur (1967), Hanstrom (1925), Kuwana (1932), Nuesch

(1957) have contributed to the knowledge of nervous system in

adult lepidopterans, but their studies were restricted to the

nerve supply of one or more organ system. Structurally Insect

brain is a compact creamish bilobed stiructure and is continuous

laterally with expanded optic lobes, it consists of various

parts as first brain or Protocerebrum which bears optic lobes.

-5-

deutocerebrum or second brain bears antennal lobes which is

divided into sensory and visceral motor areas, and thiirdly

tritocerebrum which is the smallest portion of the insect brain

containing a pair of lobes beneath the deutocerebrum of the

ventral nerve chain of segmental ganglia; the first is suboeso-

phageal ganglia, which is formed by the incorporation of the

gnathal segments, suboesophageal ganglion lies in the ventral

region of the head beneath the oesophagus, thoracic and abdominal

ganglion are all connected by longitudinal nerve cord or double

connectives to form the ventral chain, Suboesophageal ganglia

is a compound structure lying ventrally in the head region,

arising from the fusion of mandibular maxillary and labial

segments.

Typically there are three thoracic ganglia each with

five or more nerves. The number of abdominal ganglion occuring

in lepidopterans are four and the last one is always compound

being derived from the ganglia of the last four abdominal

segments.

In majority of insects some degree of fusion particularly

in the abdominal ganglion, which is smaller than the thoracic

ganglia connected across the midline (Mathur 1969, Wigglesworth

I960, Welnbormair, Pohlhanmer, Dumberger 1977) and joined with

the ganglia of adjacent segment by a pair of connectives known

as intergangllonic connectives which have no cell bodies. Basic

- 6 -

elenuants of nervous system i s neurone, derived in the course

of development. Neurones are of several types v i z . Bipolar

and Multipolar (Wigglesworth i960) . Most of the i n s e c t s have

monopolar neurone. I t has a nucleated c e l l body and a long

cytoplasmic project ions which extends to make contact with

other neurone. The ce l l body i s perikaryon while project ions

a re known as axon. The un i t of Insec t neurone system transmit

e l e c t r i c a l disturbances or impulses from one part of the body

to the o ther . They do not occur s ingly but are conjugated as

proved by Gilbert (1973), Brain as we a l l know regula tes body

metabolism, digest ion excret ion, metamorphosis, growth, repro­

duction, feeding, mating e t c . Nervous system exhib i t s cer ta in

amount of concentration with regard to the ganglia of the ventral

nerve cord.

The most extensive endocrinological s tudies was made by

William and his co-workers on the diapausing pupae of Gecropia

silkworm. In general the endocrine system of insec t consis ts

of (as described by Wigglesworth (1972) in his recent volumes)

i s ( i ) modified nerve c e l l s , neurosecretory c e l l s ( i i ) neuro-

haemal organs as corpora cardiaca and corpora a l l a t a , and

( l i i ) independent organs of i n t e rna l sec re t ion . Here i t i s

necessary to know about the neurosecretion and how neurosecretory

and ce l l regula tes d i f fe ren t hormonal balances. The term neuro­

secre t ion means d i f fe ren t things to d i f fe ren t peoples, and these

c e l l s are able to sus ta in an effect on t h e i r t a rge t organs

-7-

(Hlghman I96I, Delphin 1963). According to Gilbert: and Kerkut

(1985) in any one neurosecretory cells the secretory product is

accumulated in membrane bound vesicle which are usually though

not in all cases of rather uniform size and appearance. Neuro­

secretory cells has been studied in various insects as fine

structure of these organs was described in Rhodnius prolixus

by Kuster and Davey (1981). The allotropic activity of median

neurosecretory cells of GaUeriq mellonella^ a wax moth was

successfully observed by Muszynska - Pytel (1986). He described

that the brain allotropic hormone (ATTH) is released in Gallarla

mellonella from the median neurosecretory cells present in pars

intercerebralis. Furthermore in vitrx) neurx)secretion can be

used as a probe for locating and exploring neurohaemal sites,

measuring reasonable stores of neurohormones studying excitation,

secretion, coupling and obtaining the circulating forms of

neurohormones as said by Highnam (1961), Delphin (1963),

Treheme (I966) experimentally proved that some neurones in

insect ganglia are neurosecretory i.e. the nerve cell bodies

are modified to produce quantities of granules called elementary

granules or neurosecretory droplets. After synthesis and

condensation into granules within the neuronal perikarya the

neurosecretory material is apparently transported to neurohaemal

organs or storage via the axons. Usually nerve cells convey

uniform action by releasing specialized chemical substance

which affects other cells, neurone system is modified in distinct

-8-

ways and provides three attributes, i.e. of specificity, speed

of delivery and length of message. The release of neurosecretory

products from the membrane bound vesicles in the cytoplasm to

the outside of cell which in turn affects the target organs and

stimulate it to release the hormone essential for many vital

activities of the body, Neurohaemal organs such as corpora

cardiaca and corpora allata which are paired in some insects

but in this particular species they are fused with each other

in the cervix region. The corpora cardiaca and oesophageal

ganglion govern the function of the dorsal vessel. These are

anteriorly connected, with the protocerebrum through a pair of

nerve called procardiac nerves. The corpora allata are very

small lying ventral to and in very close association in fusion

state with corpora cardiaca with which it is connected by means

of a very short connecting duct which are not normally noticed.

The present study has been conducted with a view to

provide adequate information on the morphology and histology of

the insect central nervous system with particular reference to

REVIEW OF LITERATURE

Description of adult insect brain microanatomy still

needs some clarification. Some of the authors such as Kenyon

(1896), Bretschneider (1913, 1921, 1924 ab), Henstrom (1928),

Power (1943), BullocX and Horrldge (1965) gave a detailed review

about the anatomy and morphology of an insect brain, Kenyon

(1896), Cajal and Sanchez (1921); Schrader (1938) gave only

some details on particular type of cells which are present in

the brain region while others as Bretschneider (1914 ab),

Holste (19 23); Alverdes (1924), Jawlowsld. (1936), Bierbrodt

(1924), Rogoff (1943) have studied the morphological differences

between the mature and immature nervous system of insects.

Hanstrom (1925), Hertwick (1931), Schrader (1938), Pyle (1941)

noticed larger size of an adult brain which was due to the

increase in the number of cells and larger and more complex

n euro pile.

Brain anatomy of Monarch butterfly Danaus chrvsippus (L.}

(Nymphalidae) was studied carefully by Ehrlich and Davidson

(1961). Brain of several lepidopterans have been studied in a

generalized pattern - by Bretschneider in (1921, 1924a, 1924b),

Ehnbom (1948) distinguished the following 4 types of lepidopterous

brain: as followsi-

-10-

a) Hesperoidea and Rhopalocera, which have rounded opt ic lobes;

(b) the Macrofrenate families^ except Diepanidae and Cymatopho-

nidae (Weber 1933) which have elongated, l a t e r a l l y projecting

opt ic lobes and in which the deutocerebrum, especia l ly in

Noctuidae, i s r e l a t i v e l y large* (c) Drepanidae» Cymatophonidae,

Pyraloidea, Hepialidae and Tineioidea; which have l a t e r a l l y

compressed brain with op t ic lobes extended dorsoventra l ly

(d) Micropterygidae which have a l a rge oesophageal canal with

r e l a t i v e l y long connective and a pr imi t ive brain s imilar to tha t

of Trichoptere.

The brain of insec t va r i e s i n s i z e from t i n i e r pinpoint

to several cubic mi l l imeters . I t i s not possible to de t a i l the

novel arrangements met wilhin d i f fe ren t species because of

lacunae in our knowledge. The a t l a s of i n sec t brain prepared

by Straflsfeld (1976b), i s a landmark in the study of b ra in .

According to Vil lanes (1884) the brain of lepidopterous

i n s e c t s i s divided in the th ree pa i r s of neuromeres designated

as protocerebrum, the f i r s t b ra in , deutocerebrum, the second

brain and l a s t l y the t r i tocerebrum, the t h i rd bra in , which i s

the minutest port ion among the t h r e e .

Deta i l s on the Coleopteran bra ins are only few but

Abraham in (1969) gave a very i l l u s i v e account of the histology

of the bra ins in Dvtiscus maroinal is .

- 1 1 -

Murrary and Tlegs (1935) described the histology of an

insec t b ra in , Sa t i ja and Dass (1963) gave a deta i led account

on the s t ruc tu re of the bra in of a b e e t l e Onthophaous c a t t a .

The next region of the cen t ra l nervous system i s the thoracic

region which i s formed by the fusion of prothorax, mesothorax

and metathorax. The lepidopterans bear thorac ic nerve centers

in the mesothoracic port ion of the thorax region as i l l u s t r a t e d

by Hachlow (1931); Similar conclusions were drawn by Pflugfelder

(1958) but they did not find any appropriate endocrine glands

in the mesothorax. Pakuda (1940) observed t h a t the t ransplan ta­

t ion of the gland located near the prothoracic sp i r ac l e could

s t imulate pupation in the i so la ted hind par t s of Bombvx larvae .

This a t t r ac ted the i n t e r e s t of insec t endocrinologists to the

prothoracic glands,

Prothoracic gland sjTithesize ecdysone or substances

which have ecdysone l ike a c t i v i t y which was l a t e r confirmed by

Takeda (1976), The physiological p roper t i es of ecdysone have

been studied careful ly by Novak (1966); Sorm and Slama (1974),

which waxes and wanes under the d i r e c t control of cen t ra l

nervous systan which in t imate ly re leases a t rophic hormone

general ly known as prothoracico- t rophic hormone or bra in hormone,

and as described by Fakuda (1944), Williams (1947, 1952) i t

regresses or depresses the terminal moult on the diapause break.

According to Takeda (1977b) in Monema flavescens the neuro­

secre tory substance, the prothoracicotrophic hormone are

- 1 2 -

released from neurosecretory B type of c e l l s present in the

construct ion of the brain known as pars i n t e r c e r e b r a l i s .

Histology of prothoracic glands had been studied by

Herman (1957). The most appropriate work in the f ie ld of

neurology about the thoracic portion of the insec t Central

nervous system was done by Williams and his co-workers (1947)

on diapausing pupae of Cecropia silkworm. After these in for ­

mative discover ies they had come to the conclusion tha t the

imperative ro le of the bra in hormone i s very necessary for the

regula t ion of metamorphosis which was l a t e r on confirmed by

Williams (1946, 1952).

More recent ly other researchers have proved t h a t

prothoracic glands in the silkworm, Bomby?̂ mori (Chino, Sakurai,

Ohtaki, Ikekawa, Miyazaki, Ishibashi and Al»uki, 1974), the

tobacco hornworm, Manduca ^e^ta (King, Bollenbacher, Borst,

Vedeckis, 0 ' connor, I t tyche r i ah and Gi lber t , 1974), the cockroach,

Leucophaea maderae (Borst and Engelmann 1974; King and Marks

(1974) and the meahworm, Tanebrlo molitay produce ^^-ecdysone.

Srivastava and Singh (1973); and Hintz Poodufal (1987)

studied about the neurohaemal organs in lepidopterans and they

suggested the t ranspor t of neurosecretory granules to the gland

c e l l . On the bas is of experimentation by Srivastava, Tiwari

and Kumar (1976) i t may be assumed tha t the innervat ions of

prothoracic glands are e i t h e r involved in feeding, sensory

-13-

proprioceptive inputs to the Central nervous system or exert

a nervous inhibition on the activity, (Synthesis or release of

ecdysone) of the prothoracic gland. The whole issue of the

significance of the prothoracic gland innervation is therefore

investigative. Albrecht (1953) studied the anatomy of the

migratory locust. Locust miaratoria mlaratoides? but later on

the nervous system of Cockroach Periplanata amerlcana was

illustrated by Pipa and Cook (1959); and Shankland (1966),

As the research proceeded, people tried to find out more

details or to explore the nervous system of various insects as

Maki (1936) studied the nervous system of alder fly Chaulioides

formosanus , In so far as lepidopterans are concerned there

have been numerous general discriptions but the detailed study

of Hyalophora larvae described by Libby (1959) proved to be

very useful in neurology. As the work proceeded various other

insects of the same order have been taken into consideration,

the thoracic nervous system of Telea Polvphemus was described

by Niiesch (1957) and Eaton (1974), Eaton (19 74) also described

the anatomy of head and thorax of the adult tobacco horn worm

Manduc^ sexta. Cook (1980) studied the nerve architecture of

the oviduct in Pectinophora aosavpiella. The terminology

used for naming of the nerves is the same as that used for the

study of innervations of head and thorax as described by Eaton

(1974). Libby (1961) discussed and successfully explored the

branches of nerves in the sixth and tenth segment in males of

-14-

Hyalophora, According to Srlvastava, Tlwari and Kumar (1976)

innervation of Prothoracic gland is found in at least five

insect orders, while the function of these nerves have been

variously suggested by Lafon, Gazal, Roussel (1976); Goldsworthy

(1971); Millis Greenslade, Couch (1966); Uroman Kalpanis Robbinc

(1971), Walker Bouley (1971); Vanthan der lea (1965).

The Central nervous system of insects also includes the

abdominal ganglionic masses. Each ganglion which is somewhat

bulb like in shape is connected by interganglionic connectives

as experimentally proved by Siegler and Burrows (l979).

Newport, (183 4); Brandt 1879; Paterson, (1899), Buxton

(1917) exhibits a certain amount of concentration with regard

to the ganglia of the ventral nerve cord. The conditions of

thoracic and abdominal ganglion differ greatly as found in

Hepialus in which three thoracic and five abdominal ganglia

was observed. In Tinea pellipnella (Micropterygidae) and some

other insect spp., the 4th and 5th abdominal ganglia are fused

into a large common centre. The majority of lepidopterans are

characterised by two thoracic and four abdominal ganglia; those

of the raeso- and raetathorax are fused and the abdominal ganglia

lie in the 2nd to 6th abdominal segments. While in Fumea

intermedia and others there are four abdominal ganglia in both

sexes. The terminal ganglion in some insects gives out several

pairs of nerves as shown by Libby (1959) in Jg. cecropja. The

-15-

intemal morphology of lepidopterans described by numerous

workers as in one of the most complete account given by

Osteo and Helms (1976) in Laxaarotls albicost^ belongs to

the family Noctuidae, Ehrilch and Davidson (1961) gave gross

anatomy of Danau;̂ plexippus« which forms the baseline in the

study of lepidopteran nervous system, and proved to be very

successful in the foregoing discussion.

Neurosecretion has recently been the subject of rather

great interest and prominent work in the field of neuro­

secretion was done by Van der Kloot (I960), Gane (1966). The

term neurosecretion was defined differently by different peoples.

According to Van der Kloot (i960). Neurosecretory cells are

those nerve cells which when examined microscopically shows

signs of secretion. Some of these cells are involved in the

release of hoirmones, while other release substance which

effects only for short duration. Some neurones in insect

ganglia are neurosecretory i.e. the nerve cell bodies are

modified to produce neurosecretory droplets. Most of the work

on neurosecretion is done electron microscopically. Some evi­

dences reveal that the ganglia of the ventral nerve cord

contains many neurosecretory cell, (Nayar 1954, Wigglesworth

1955a, Fraser 1959, Geldiay 1959). In insect number of different

neurosecretory cells has been described.

MATERIALS AND METHODS

Eggs of D^naus chrvs lppus (L) (Monarch b u t t e r f l y ) were

col lected from plants of AsclepJas curraasavlca (Akawwa) from

t h e Universi ty campus and Aligarh Port , and rear ing was done

under laboratory condi t ions .

Adults were kept i n a cage in a basement laboratory

receiving daylight but never d i r e c t sunl ight . Suppl«nentary

i l luminat ion was derived from 60W bulb placed away from one

side of the cage and run overnight during winter season. The

temperature during night was e s sen t i a l for reasonable fecundity

and adult l i fespan . Adults were fed on cotton soaked sugar

solut ion and adult l i fespan was about 20-22 days with the

temperature 29 + I 'C ,

Materials were drawn from the maintained standard

cu l t u r e .

For morphological and anatomical observations the

i n sec t s were anaesthesized and were dissected in Normal Saline

under the binocular microscope. Methylene blue proved to be

very sa t i s f ac to ry in d is t inguish ing the ganglion and i t s

innervat ion. For h i s to log ica l s tud ies material was taken and

dissected in physiological s a l ine and then kept in Bouins fluid

(alcoholic) for about 12 h r s ; dehydration was done with different

-17-

alcohol ic grades. Material was cleared in xylene and absolute

alcohol/ with a r a t i o of 50i50 and f i n a l l y t ransferred to pure

xylene used as c lear ing agent. The claved material was t r a n s ­

formed t o paraffin wax of 50-60 m.p. for about 4 h rs . Blocks

were cut at 3 xi with a rocking microtime.

For s ta ining purposes Heidenhain's i ron haematoxylin

and alcoholic Eosin were used for cytoplasmic and nuclear

d i f f e r e n t i a t i o n . Complete dehydration was ensured before

mounting of the material in D.P.X, mountant for microscopic

examination.

Results and Discussion

The insect Danaus chrysippus (L) undergoes following

biological stages to complete its life cycle,

(1) :^3G STAGEt The egg is generally laid on the lov;er

surface of the leaf; It may also be laid, more rarely on the

upper surface. It is generally glued to the surface near the

margin of the leaf on one side of the midrib. It is creamy

white nearly globular, slightly longer along its longitudinal

apex. The base is round and flat and each egg is laid singly

and one egg on one leaf only, as a irule, but in one case seven

eggs were found on one leaf. Big or small leaves are indiscri­

minately choosen for egg-laying. The surface of the egg is

marked by ribs running from the basal periphery and converging

into the apex of the egg. Between these longitudinal ridges

there are faint parallel striations situated one below the

other. The longitudinal ridges do not meet each other at the

apex but leave a micropylar area reticulated. The egg is set

vertical on leaf surface,

THE NSWLY HATCHED LARVAt The larvae on hatching from the eggs

at once attack the empty shells and in nearly all cases devour

them to well near the bases begining from the apex and after­

words proceed to feed on tender leaves by the margin. It is

cylindrical in shape almost uniform in dimension throughout.

- 1 9 -

t a p e r i n g v e r y s l i g h t l y p o s t e r i o r l y . The head i s l a r g e r t h a n

t h e p r o t h o r a c i c s e g m e n t , r o u n d i s h d e f l e x e d . S u r f a c e i s s h i n i n g ^

d o r s a l s u r f a c e h a v i n g an i n v e r t e d Y- shaped s u t u r e . The t h o r a c i .

l e g s a r e s h i n i n g , w e l l d e v e l o p e d d i s t i n c t l y j o i n t e d and g r e y i s h

b l a c k i s h c o l o u r e d . The c o l o r o f t h e body i n c l u d i n g t h o r a c i c

r e g i o n i s n c r e a m y w h i t e , a n a l c l a s p e r s have h o o k l e t s . I n t h e

f i r s t i n s t a r l a r v a t h e s i z e i n c r e a s e s , o n l y c r i m s o n i s h t r a n s -

v e r s b a n d s have d e v e l o p e d from s i d e t o s i d e on each segment .

V e n t r a l c o l o r a t i o n l i g h t y e l l o w i s h , t h a n i n s e c o n d , t h i r d ,

f o u r t h and f i f t h i n s t a r l a r v a e o n l y t h e s i z e i n c r e a s e s .

PUPA; L a r v a e p u p a t e s g e n e r a l l y on t h e f o u r t h o r f i f t h

day by c a s t i n g o f f i t s l a s t m o u l t . The pupa i s suspended

v e r t i c a l l y head downwards from t h e p o i n t o f a t t a c h m e n t by

i t s b l a c k c r e a m a s t e r whose hooked h a i r s a r e e n t a n g l e d i n a

pad of sillf. woven on t h e s u r f a c e , A day a f t e r p u p a t i o n

g o l d e n s p o t i s s een on t h e pupa r ium,

ADULT: I n c u b a t i o n p e r i o d n i s abou t two d a y s . B u t t e r f l y

emerges by b u r s t i n g t h e l o w e r o r head end of t h e pupa and

hangs on t h e empty pupa c a s e w i t h c r i m p l e d wings and s h o r t

t h i c k abdomen. I n a b o u t h a l f an h o u r wings expand and

h a r d e n and abdomen l e n g t h e n s . P e r i o d of l i f e c y c l e i n ho t

w e a t h e r i s 20 d a y s (Egg p e r i o d 3 d a y s , l a i rva^ p e r i o d 10

d a y s , pupafe p e r i o d 7 d a y s ) .

-20-

THE NERVOUS SYSTEM}

The Insect nervous system is divided into (a) central

Nervous system (b) Stomodeal Nervous system and (c) Peripheral

Nervous system.

At the moment the study of the nervous system of

Danaus chrvsippus (L) is only confined to the Central Nervous

System, Here in this foregoing discussion only the anatomy

and morphology of this very system has been taken into

consideration,

THE CENTRAL NERVOUS SYSTEMi

The central nervous system of Monarch butterfly

D. chrvsippus (L) consists of Brain, Suboesophageal ganglion

and the Ventral nerve cord.

The nervous system of D, chrvsippus encircles the

pharynx and persists along the midventral line below the

alimentary tract in the thoracic and abdominal portions. The

present author has observed that in the larvae stage of

monarch butterfly the number of ganglia is according to the

number of body segments but as the stage advances and the

catterpillar moves towards the adult stage the number of

ganglionic masses fuses. In the advance stage a greater

degree of cephalization is observed. The first part of the

insect nervous system is.

- 2 1 -

BRAIN: (Br) Brain l i e s j u s t above the oesophagus between

the supporting apodemes of the tentorium. I t i s somewhat

creamish in color and a compact mass without conspiquous

prominences. Among the chief ear ly wr i t e r s on the s t ruc tu re

of the brain are those of Vialanes (1886-87), Haller (1905),

Janet (1905), Jonessen (1908). Brain occupies major portion

of the cranium. I t l i e s t ransverse to the head capsule. I t

i s the dorsal ganglionic cent re of the head and i s formed by

the coalesence of the f i r s t th ree neuromeres of the embryo.

This t h ree fold d iv is ion i s maintained in the completed organ

which divides in to corresponding regions, which are designated

as Protocerebrum or f i r s t b ra in , Deutocerebrum or second brain

and Tritocerebrum or the th i rd brain respec t ive ly . However

these th ree subdivisions of rthe bra in are not d«narcated

ex te rna l ly but are ac tua l ly d i f fe ren t i a ted on the Igasis of

the nerves or ig ina t ing from than. The Brain of D. chrvslppus

was also studied by Ehrlich and Davidson (1961). Brain i s a

bilobed s t ruc tu re with two bulding ganglia on i t s e i the r

s ide as shovm in Fig. 1. The l a t e r a l port ion of the brain

i s depressed but i t s dorsocaudal region i s s l i g h t l y raised

to form an arch over the stomodeum.

PROTOCEREBRUM (IBr)i Protocerebrum in D. chrvsippus i s

dorsal i n posi t ion and occupies la rge portion of insec t brain

as shown in Fig. 1 and Fig. 15, This comprises the cent ra l

- 2 2 -

complex, pars i n t e r ce reb ra l i s^ corpora pedunculate and

op t ic lobes . I t s two lobes have undergone fusion which i s

v i s i b l e ex terna l ly by a cons t r i c t ion along the mid-longi­

tud ina l groove Fig. 1. The cen t ra l complex i s not very

prominent but pars i n t e r c e r e l o r a l i s (Pi) i s very conspicuous

under the l i g h t microscope Fig. 1. I t i s the anteromedian

c e l l u l a r area of the brain occupied by motor c e l l s and

neurosecretory c e l l s . The protocerebrum d o r s o - l a t e r a l l y

gives out a pa i r of s tout nerves going to the l a t e r a l o c e l l i ;

Pi is tological ly the f i r s t brain bears a pa i r of la rge rounded

opt ic lobe (Op.L) and oce l l a r cen t re . The opt ic center

invera tes the eye. Each opt ic lobe i s demarcated from the

protocerebrum along a d i s t i n c t external cons t r i c t ion (Cons.)

Fig. 3. The opt ic lobes according to Chauthani and Callahan

(1967b) in H. zea begin to d i s t ingu ish i t s e l f in the prepupal

s t age . The opt ic ganglion bears lamina, (L) medulla (M) and

lobul la Fig, 4, The neuropiles of the op t ic lobe and the

inne r lobula are conspicuously s t r a t i f i e d and arranged in

columns based upon the ca r t r idges of r e t i n a l elements Fig. 4.

The laminal l in ings are also c l ea r but the medullar portion

i s fake. The most conspicuous port ion of the protocerebrum

are corpora pedunculate (CP) Fig. 1. Each of these s t ruc tures

are semicircular with a s l igh t cup l i k e depression, the

calyx (Cy) and a branching s ta lk (S) the peduncle in the

protocerebral neuir)pile. There are two calyces in each brain

hemisphere.

- 2 3 -

DSUTOGEREBRUM (I I Br) i Behind the Protocerebrum l i e s a deuto-

cerebrum or the second brain which i s vent ra l in pos i t ion .

This i s the middle part of the bra in which i s smaller i n

s ize Fig. 15. I t can however be iden t i f i ed by the antennal

lobe, which bears antennal nerves supplying to the antenna.

In the vent ra l region of the brain the two opposite deuto-

cerebral lobes touch each o ther , and the antennal nerves

a r i se from t h i s very region of the bra in , Abraham (19 67)

reported the presence of a th in and a th ick f ibre system in

the antennal glomeruli. But in Spilachn^ viqintioctomaculata

the antennal lobe lacks the glomerular the fibrous zones.

Bahadur and Srivastava (1968) i n Prodenia l i t u r a have shown

large sized deutocerebrum. The antennal lobes are separated

by some dis tance but t h e i r coramisures l i e within the substance

of the bra in . The antennal lobes have motor and sensory

areas Fig, 15.

TRITQCEREBRUM ( I I I Br): This i s the smallest portion amongst

the t h r ee . I t l i e s ventra l to the antennal lobe from which

i t i s f a in t l y demarcated. These are connected with the pro­

tocerebrum on dorsal region of the bra in . I t s pos te ro - l a t e ra l

par t s are drawn downswards to l ink with t he sub-oesophageal

ganglion.

SUBOESOPHAGEAL GANGLIQNt I t i s a compound mass of segregated

ganglia of gnathocephalic segments. The suboesophageal

ganglionic mass lying below the pharynx i s formed by the fusion

-24-

of paired mandibular, maxillary and labial ganglia. Ehrlich

and Davidson (1961) in Q, chrvsippus have recorded absence of

mandibular nerves. Functionally it probably works in close

association with the supra-oesophageal brain (Tyrer and

Gregory (1982), Stransfeld (1976), but morphologically it

resembles thoracic ganglia in nerve distribution Pig, 15,

VENTRAL NERVE CORD (VNC): The ventral nerve cord of

D. chrvsippus bears six dull cream coloured ganglionic masses

arranged in a linear fashion along the mid ventral longitudinal

line of the trunk. Each ganglionic mass is connected by an

interganglionic connectives Fig. 16,

THORACIC G^^GLIQN: In the thoracic portion there present

three ganglionic masses which are designated as Prothoracic

ganglion, mesothoracic ganglion and metathoracic ganglion

respectively.

PROTHORACIC GANGLION (Ptg): It is the first ganglion of the

ventral nerve cord. (1 Gng.). It is smaller than the combined

meso and metathoracic ganglion Fig. 6, Pig, 16 Chauthani and

Callahan (1967a) in H, zeg have shown it somewhat displaced

from its original position in the mesothorax. Anteriorly it

is connected with the suboesophageal ganglion by a fused

pair of ventral nerve connectives.

-25-

Two short but very stout connectives extend

posteriorly from the prothoracic ganglion to connect it

with the second thoracic ganglionic masses. This is the only

place in the nerve chain of the adult where the paired

ganglionic connective maintain their separate identity other­

wise they are completely fused with each other. However,

the paired nature of interganglionic connectives is maintained

in the larval stages as shown by Chauthani and Callahan

(1967b). in H, zea. The nerve distribution of prothoracic

ganglion is simply illustrated in Fig, 21. As shown in

Fig. 20, the thoracic ganglion of the ventral nerve cord

bears 5 pairs of nerves and a connective and these nerves

are distributed to various organs.

MESO META THORACIC GANGLIONt These ganglia are somewhat

barrel shaped in structure. This is a composite structure

formed by the fusion of meso-, and metathoracic ganglia

together with first two abdominal ganglia. They are connec­

ted with each other and a line of demarcation between the

two is observed very clearly under the light microscope as

revealed in Fig, 11. The cells are very prominent near the

connection Fig, 11. Fig. 12. Anteriorly the mesothoracic

ganglion bears neuromeres Fig. 10. Which are prominent

Fig, 6, While the posterior view of the thoracic ganglion

when seen microscopically, does not show any clear cells.

-26-

The meso- and metathoracic ganglia show ganglionic core

which i s the cen t ra l mass and i t bears ganglionic c e l l s at

i t s periphery. The Central mass has g l i a l c e l l s Fig, 11,

Neuroanatomical s tudies of i n s e c t segmental ganglion

have lagged behind physiological s tud ies . One of the few

organisat ional p r inc ip les f i r s t elaborated by Binet (1894)

r e l a t i n g to the d i s t r i b u t i o n of the motor elements pre­

dominantly in the dorsal par t and sensory elements in the

ven t ra l portion of the ganglionic core . This general izat ion

was broadly substant ia ted by the c l a s s i c a l methylene blue

s tud ies by Zawarzin (1924a,b), on the dragon f ly .

ABDOMINAL GANGLIA; (Abd.g,) : The ven t ra l nerve cord in the

abdominal region bears 4 ganglionic masses. These masses

are somewhat c i r c u l a r and creamish in colour and attached with

each other in a chain l i k e manner. Each abdominal ganglion

gives out two pa i rs of l a t e r a l nerves to the segment concerned.

Fig. 15, These nerves innervate v e n t r o - l a t e r a l muscles of the

abdomen and the d iges t ive organs. The f i r s t 3 ganglia are

button shaped and are s i tuated in the pos te r io r halves of

2nd, 3rd and 4th abdominal segments. The nerve d i s t r i bu t i on

of the an te r io r 3 ganglia i s s imi lar Fig. 15, Each ganglion

i s encircled by a membrane known as Neurilemma (Nlm) and has

a ganglionic core (gc) . The c e l l s are seen in c lu s t e r s at

the peripheral region of the ganglion Fig, 14. The terminal

ganglion of the abdominal region of ven t ra l nerve cord i s

-27-

somewhat bulb like in structure. This ganglion is composite

structure made up of 6th, 7th and 8th abdominal segments.

This ganglion differs in size with the other three ganglionic

masses, and this ganglion is complicated in the sense that

it bears more than two pairs of nerves Fig, 16. In males

thus terminal ganglion gives out 5 paired nerves. The first

pair represents the typical segment anterior lateral nerve

innervates dorsal diaphragm, heart segmental muscles and

spiracles. Similarly 2nd pair is typical post lateral nerve

supplying to the muscles. The 3rd pair of nerve arises

posteriorly to the 2nd pair and travel in the postero lateral

direction. The other pairs goes to respective reproductive

organs, Libby (1961) in H, cecropiq. shows ten pairs of

nerves arising from the tenrdnal ganglion, three pairs each

for 6th, 7th and 8th segments and one pair for the reproductive

organs and the genitalia.

^n female there is no differentiation in the inner­

vation but only the point of dissimilarity is in the size of

the terminal ganglion. The shape is bulb like and size is

smaller than that of the males. The first pair of nerve is

fairly thick whose branches innervate the sixth segment. Other

pairs go to the reproductive tracts and the genital organs.

'•' ' / • '

i •;' Oc: - ' jr-" ' '> .

\ •ft^

REFERENCES

A l v e r d e s , A. ( 1 9 2 4 ) . Die Wirkung e x p e r i m e n t e l l e r E i n g r i f f e

i n s b e s o n d e r a d e r Blendung auf den h i s t o l o g i s c h e n

Bau d e s I n s e k t e n g e h i m s

2 . Morp. u . Okol T i e r e . gt 1 8 9 - 2 1 6 .

A l b r e c t , P .O . ( 1 9 5 3 ) . The anatomy of t h e m i g r a t o r y l o c u s t ,

A t h l e n e , London.

Abraham, A. ( 1 9 6 9 ) . E l e c t r o n m i c r o s c o p i c a l o b s e r v a t i o n s

on t h e m e d i a l n e u r o s e c r e t o r y c e l l s i n t h e b r a i n

o f w a t e r b e e t l e D v t i s c u s m a r g i n a l i a

Z. Mikr . A n a t . F o r s c h QO^, 4 6 9 - 4 8 4 .

B r a n d t , E, ( 1 8 7 9 ) . V e r g l e i c h e n e l - a n a t o m i s c h e u n t e r -

suchungen Uber d a s Nerven sys t em d e r L e p i d o p t e r a n .

Hbr. Soc . e n t . R o s s . 1^ , 6 8 - 8 3 .

B r e t S c h n e i d e r , F . ( 1 9 1 3 ) . Der C e n t r a l k o r p e r und d i e p i l z f o r -

migen k o r p e r d e r I n s e k t e n ,

Z o o l . Anz. 61I 5 6 0 - 5 6 9 .

Buxton , P.A. ( 1 9 1 7 ) . On t h e P r o t o c e r e b r u m of M i c r o p t e r y x

T r a n s . En t . Soc . Lond. 1 2 1 2 : 1 1 2 - 1 5 3 .

B r e t s c h n e i d e r , F . ( 1 9 2 1 ) . Uber d a s G e h i r n d e s Wol f smi l ch -

Schwarmers ( D e i l e p h i l a e u p h o r b i a e ) .

J e n a . Z. N a t u r w i s s . ^ t 4 2 3 - 4 6 2 .

- 2 9 -

*Bretschneider^ F, 1924(a) , Uber d i e Gehirn e ines Baren

sp inne r s (Call imorpha dominula/ d i e jungf e r ) .

Jena . Z. Naturwisst 60: 147-173.

• B re t s chne ide r , F, 1924(b) . Uber d i e Gehirn des Eichen-spinners

und des Se idensp inners (Lasiocampa quercus L. und

Bombvx mori . L,

Jena . 2 . Naturwiss . 60: 563-578.

B ick ley , W,E. (1942) . On t h e stomodeal nervous system of

i n s e c t s .

Ann. Entomol. Soc. Amer. 3 5 : 3 43-54.

*Biert>rodt, E, (1942) . Der Larvenkopf von Panorpa communis L.

und se ine Verwandlung mit besonderes Berucksicht igung

des Gehims und d e r Augen.

Zool. J b . Abt. Anat. u . Ontpq. 68 : 49-13 6.

Bullock^ T.H. and Horr idge, G.A. (1965) . S t r u c t u r e and Function

i n t h e nervous system of I n v e r t e b r a t e s .

W,H, Freeman and Co; San F ranc i sco .

B o r s t , D.W, and F. Engleman (1974) . In v i t r o s e c r e t i o n of

-ecdysone by p r o t h o r a c i c glands of a hemimetabolous

i n s e c t s , Leucophaea moderae ( B l a t t a r i a )

J . EXP. Zool. iS.9t 413-419.

- 3 0 -

* C a j a l , S.R. and S a n c h e z , D. ( 1 9 2 1 ) . S o b r e l a e s t r u c t u r a de

l o s c o n t r o s o p t i c o s d e l o s i n s e c t o s .

Rev. C h l l . P i i s t . n a t . S a n t i a g o 2 5 : 1 -18 .

C a z a l / P. ( 1 9 4 6 ) . R e t r o c e r e b r a l e n d o c r i n e g l a n d s i n i n s e c t s .

B u l l . B i o l . F r , B e l g , £ 0 : 4 7 7 - 8 2 , 4 8 3 . 6.

Colhoun , E,H, ( 1 9 6 3 ) . The p h y s i o l o g i c a l s i g n i f i c a n c e of

a c e t y l c h o l i n e i n i n s e c t s and o b s e r v a t i o n s upon

o t h e r p h a r m a c o l o g i c a l l y a c t i v e s u b s t a n c e s . I n :

ADVANCES OF INSECT PHYSIOLOGY Vo. 1 , Eds - J .W.L.

Beament, J . E, T r e h e r n e and V.B. Wigg leswor th

(Academic P r e s s , London and New York) P : 1-45.

C h a u t h a n i , A.R. and C a l l a h a n , P . S . ( 1 9 6 7 ) . The n e r v o u s sys tem

of an i n s e c t Rhodnius p r o l i x u s ( H « n i p t e r a ) . 1 1 .

The c e n t r a l g a n g l i a .

Q u a r t . J . m i c r . S c i . 1001 2 9 9 - 3 1 5 .

Ch ino , H . S , , T. S a k u r a i . , N. O h t a k i , M. M i y a z a k i , I s h i b a s h i

and H. Abuki ( 1 9 7 4 ) . B i o s y n t h e s i s of - e c d y s o n e by

p r o t h o r a c i c g l a n d i n v i t r o .

S c i e n c e 1 8 3 : 5 2 9 - 5 3 0 .

Cook, B . J , , Thomson, J . M . , and S h e l t o n , W. D. ( 1 9 8 0 ) . Some

s t r u c t u r a l and f u n c t i o n a l p r o p e r t i e s of n e r v e s and

m u s c l e s i n t h e o v i d u c t o f t h e p i n k bo l lworm moth.

' I n t . J . I n v e r t e b r . Reorod . Z> 3 5 1 - 3 6 2 .

-31-

Du Porte, E,M. (1915). On the nervous system of the larva of

Sphlda obljqua Walker.

Trans. Rov. Soc. Can, g,: 225-53.

Delphin, F. (1963). Histology and possible functions of

neurosecretory cells in the ventral ganglia of

Schistocerca qreqarla (Forsk).

Nature. 200i 913-915.

Ehnbom, K. (19 48). Studies on the central and sympathetic

nervous system and some sense organs in the head

of neuropteroid insects.

Qpusc. Entomol. Suppl. . 2.1 162.

Ehrlich, P.R. and Davidson, S.E. (1961). The internal anatomy

of the monarch butterfly panaus plexippus. L.

(Lepidoptera t Nymphalidae)

Microentomoloqy, 24t 85-133.

Eaton, J.L. (1974). Nervous system of certain abdominal

segments and the innervation of the male reproduc­

tive system and genitalia of Hvalophora cecroPia

(Lepidoptera s Saturnidae).

Ann. Entomol. Soc. Am. 54» 887-896.

Fakuda, S. (1940). Induction of pupation in silkworm by

transplanting the prothoracic gland.

Proc. Imp. Acad. Tokvo: jj6: 414-416.

- 3 2 -

Pakuda, S. (1944) , The hormonal mechanism of l a r v a l molt ing

and metamorphosis i n t h e silkworm.

J . Fac. S c i ; 6j 447-53 2.

F r a s e r , A. (1959) . Neuroscere to ry c e l l i n t h e obdominal

gang l i a of l a r v a e of L i c i l i a c a e s a r ( D i p t e r a ) .

Q. J l r microsc . Sc i . 100: 395-399.

Geldiay, S. (1959) . Neuroscere tory c e l l i n t h e gang l ia of t h e

roach Blabeirus c r a n i i f e r B io l . Bu l l , mar, b i o l . Lab.

v/oods Hole. 117: 267-274.

Gabe, M. (1966) . Neurosce re t ion

Pergaraon Press Oxford.

Goldsworthy, G. J . , Mordue, W, and Gu l t e l ch . J . (1972) . S tud i e s

on i n s e c t a d i p o k i n e t i c hormones

Gen. Comp. Endocrinol^ 18: 545-551.

G i l b e r t , L . I . and King, D.S. (1973) . Physiology of growth

and development endocr ine a s p e c t s . In M. Rockstein

( e d . ) The Physiology of i n s e c t s V . I . London, Academic

Press P. 249-3 70.

G i l b e r t , L . I . and Kerkut , G.A, (1985) . Comprehensive i n s e c t

phys io logy b i o - c h e m i s t r y and Pharmacology (195)

V o l . 5 . (Nervous system: S t r u c t u r e and motor func t ion .

Dep t t . of Biology, U n i v e r s i t y of North Carol ina

U.S.A. Pergaman P r e s s .

-33-

*Holste, G. (1923). Des Gehirn von Dytlscus marglnails

L«Z. Miss. Zool., 120t 251-280.

Hanstrom, B. (1925). Camparison between the brains of the

newly hatched larva and the imago of PIeris brasslcae.

Ent. Tldsskr.. 46: 43-52.

•Hanstrom, B. (19 28). Vergleichende Anatomie des Nervensystems

der wirbellosen Tiere, Berlin Julius, Springer.

•Hertwick, H. (1931). Anatomic und Variability des

Nervensystems und der Sinnesorgane von Drosophila

melanoqaster (Meigen)

Z. Wiss. Zool. . 139: 559-663.

*Hachlow, V. (1931). Zur Entwicklungsmechanik der Schmetterlinge.

Withelm Roux Archiv. Ent. mech.. 125: 26-49.

Hillemann, H.H. (1933). Contribution to the morphology of the

nervous system of the mature larva of Papilio

polvxenes Fabr. (Lepidoptera: Papilionidae).

Ann. Entomol. Soc. Amer; 26: 575-85.

Hess/ A. (19 58). Central and Peripheral nerve fibers in

Perlplaneta.

J- Morph. 103, 479-502.

Quart. J. Micro. Sci. . 9^: 334-340.

-3 4-

Highnam, K.C. (1961) , The h i s t o l o g y of t h e n e u r o s e c r e t o r y

system of t h e a d u l t female d e s e r t l o c u s t ,

Sch l s toce rca q r e q a r i a ,

Q. J l . Mlcrosc . S c i , . l ^ t 27-38,

Herman, W, S . , G i l b e r t , L . I . (1965) , M u l t i p l i c i t y of neuro­

s e c r e t o r y c e l l s t y p e s and groups i n t h e b r a i n of

s a t u m i d moth Hvaloohora c e c r o p i a . L.

Na tu re . 205t 927-929.

House, P. E. (19 77) , Brain s t r u c t u r e and behaviour i n i n s e c t s .

Ann. Rev. Entomol. . 2Q.t 3 59-3 79.

*Hint2e-pooufa l ,C, (1987) , S tud i e s on neurohaemal organs i n

Lepidoptera ) Untersuchungen an Neurohaemal organen

von Lepidopteron , M i t t e i l u n g e n d e r Deutschen

G e s e l l s c h a f t fu r Allgemeine and Angewandte

EntomolQQie. ^ (1-4) 217-222.

Imms, A.D. (1957) , A gene ra l t ex tbook of entomology 9 t h e d , ,

r ev i sed by 0,W, Richards and R.G, Davies , London,

Methuen,

* J a n e t , C. (1905) , Anatomie de l a t e t e du Las ius n i g e r ,

Limoges - Pages 1-40,

•Jawlowski , H. (193 6 ) , Uber den Gehirnban d e r Kafer

a. [toCPhQ. QKQi. TXgrg; Hi 6 7 - 9 1 .

-3 5-

Kenyon^ C.F. (1896) , The b r a i n of t h e Bee.

J . Comp. Neurology? ^ : 133-210.

Kuwana, Z, (193 2 ) , Morphological s t u d i e s of t h e nervous

system of t h e silkworm. 1. The inneirvat ion of

t h e d o r s a l v e s s e l .

B u l l . S e r i c u l t . Exp> S t a . Chosen? g : 109-20.

King, D . S , , Marks, (1974) . The s e c r e t i o n and metabolism of

-ecdysone by cockroach (Leucophaea mad era e)

t i s s u e s i n v i t r o .

U £ Q Sgjfflgg/ 15.* 147-154.

Kus te r , J . E , , Davey, K.G, (1981) . F ine s t r u c t u r e of t h e

abdominal n e u r o s e c r e t o r y organs of Rhodnius

PffgU^WS* S t a l .

gan. ^ . ZQQL, ^ i 765-770.

Libby, J . F . (1959) . The nervous system of c e r t a i n abdominal

segments of t h e Cecropia l a r v a , (Lepidoptera

S a t u m u d a e ) .

Ann. Entomol. Soc. Amer., 5^ : 469-480,

Libby, J . L . (1961) . The nervous system of c e r t a i n abdominal

segments and t h e i n n e r v a t i o n of t h e male r e p r o ­

d u c t i v e system and g e n i t a l i a of Hyalophora cecropia

(Lep i : S a t u m u d a e ) .

Annt Entomoli ?0<?i A^*/ M» 887-896,

- 3 6 -

Maki, T, (193 6 ) , S tud ie s of t h e s k e l e t a l s t r u c t u r e , muscula ture

and nervous system of t h e a l d e r f l y ^ Chauloldes

fQgroggnug Pe t e r son .

Mem. Fac. S c l . A a r l c . Tlahokra Imp. Univ . . 161

117-243.

Mathur, L.N.L. (1967) , Morphology of t h e nervous system of

noc tu id l a r v a e Prodenla l l t u r a Fabr , and

T r l c h o p l u s l a n i . Hubner,

IndX§fi J j SptQnK?lw 22.t 25-33 .

Mathur, L.N.L. (1969) . Morphology of t h e nervous system of

a d u l t Pro<?epAa l l t u r a

Ann. Ent> Soc. Am.. 62» 525-529.

Muszynska-pyte l , M. and Szo la j ska , E, Abs t r ac t of t h e

XII European conference of compar l t lve Endocrinology,

p . 115, Belgrade .

Newport (183 2 ) . On t h e nervous system of Sphinx l i q u s t r i (L)

and on t h e changes which i t undergoes dur ing appar t

of metamorphosis i n i n s e c t s .

P h i l l . T rans . Rov. Soc. Lond, 122: 383-398.

Nayar, K.K. (1954) . ;rhe n e u r o s e c r e t o r y system of t h e f rv i i t f l y

Chaetodaeus c u c u r b i t a e Coq . l . D i s t r i b u t i o n and

d e s c r i p t i o n of n e u r o s e c r e t o r y c e l l i n a d u l t f l y ,

PgQgi ;tn<aiat?. Aga^t §gAt Bt i ^ : 138-144.

-3 7-

*Nuesch, H, (1957). Die Morphologie des Thorax von Telea

Polyphemus cr. (Lep.) II. Nervensystem.

Zool. Jahrb. (Anat), 21* 615-42.

Novak, V.J,A. (1966). Insect hormones

Methuen. London. £?£.

Paterson, W. (1900). Beitrage zur Morphologie der Lepidopteren

Msm. Acad. Sell ?t. p^t^fs^?«> (s). 2.̂ 144 pp.

Pyle, R, W. (1941). Changes in the nervous system of Lepidoptera

during metamorphosis.

Thesis, Harvard University.

Paterson (1899) Bietrage zur Morphologie der Lepidopteran,

Mem. Acad. Sci. St. Petersb; 2.*

Power, M, E. (1943). The brain of Drosophjla melanoqaster.

J. Morph., 21* 517-559.

•Pflugfelder, 0. (1958). Entwicklungphysiologie der Inaekten.

490 pp. Akad. Verlagsges. Geest & Portig, Lei.

Pipa, R. and Cook, E. (1959). Studies on the hexapod nervous

system, 1, The peripheral distribution of the

thoracic nerves of the adult Cockroach. Periplaneta

Ann. fihtQinol. jSoCi Am* 0-52.* 695-710.

- 3 8 -

Roonwal, M.L, (1936). S tud ie s on t h e embryology of t h e a f r i can

migra to ry l o c u s t , Locusta t q io ra to r i a mjq ra to ides .

1, The e a r l y development wi th a new theory of

mul t iphased g a s t r u l a t i o n among i n s e c t s .

P h i l . Trans . Roy. Soc. B. 226, 391-421.

Roonwal, M.L. (193 7 ) . S tud i e s on t h e embryology of t h e a f r i can

mig ra to ry l o c u s t , Locusta .m. m i o r a t o i d e s Reiche and

Frm. ( o r t h : a c r i d i d a e ) 1 1 . Organogeny.

P h i l . T rans . Roy. Soc. B i 227: 157-224.

Rogoff, W.M. (1943) . The anatomy and metamorphosis of t h e

c e p h a l i c gang l i a of t h e mosqui to .

T h e s i s , Corne l l U n i v e r s i t y .

Raabe, M. (1982) . I n s e c t Neurohormones.

New York, Plexum P r e s s .

Swaine, J.M. (1920) , The nervous system of l a r v a of

Sthenopis t h u l e s t r o c k e r .

Can. Entomol. . 52i 275-283.

•Schrader , K. (1938) . Untersuchungen uber of Normalent-

wicklung d e r G e r h i m s und Gehin t r a n s p l a n t a t i o n e n

be i de r Mehlmotte Ephest ia k u h n i e l l a Z e l l e r nebst

e i n i g e n Bemerkunga uber das corpus a l l a tum.

QJQU ^?ntrf l l t?lg, ^ t 52-90.

-39-

Schmitt, J.B, (1954). The nervous system of the pregenltal

abdominal segments of some Orthoptera,

Ann. Entomol. Soc. Am.. £1% 677-682.

Srivastava, B.P, (19 59). The morphology of the nervous

system of the full grown larva of Leuclnodes

orbonalis. Guen (Lepi t Pyraunstidae).

Zool. Anz.^ 1631 288-29 7.

Schmitt, J.B. (1962). The comparative anatomy of the insect

nervous system,

Ann. Rev. Sntomol.. 7: 13 7-156.

Satija, R,C,7 Dass, B. (1963), Histological studies on the

brain of Onthophaous catta (E). (Coleop)

Res. Bull. Punjab Unlv, (Zool), 14_: 231-241.

Shankland, D.L, (1966), Nerves and muscles of the Pregenital

abdominal segments of the american cockroach,

J. Morphol.. 112 * 353-386,

S r l v a s t a v a , V . S . ; Singh, Y.N. (1973) , His tomorphological

changes i n t h e b r a i n and nerve cord of t h e Ind ian

wasp P o l i s t e s habraeus Fabr . (Hymenop : Vesipidae)

dur ing metamorphosis,

Z. Morphol. T i e r e , 75» 125-135.

- 4 0 -

Sorm, F . , Slama, K. (19 74 ) . Chemistry and physiology of

ecdyso ids Pi 303-387 i n K. Slama, M. Romanuk

and F Sorm, (Eds) , I n s e c t hormones and

b i o a n a l o g u e s . Sp r inge r , 53 4-549.

S r i v a s t a v a , K . P j , T i w a r i , R.K. and Kumar, P. (1976) . Effect

of s e c t i o n i n g t h e p r o t h o r a c i c gland nerves i n t h e

l a r v a of t h e lemon b u t t e r f l y P a p i l i o demoleug

(Lep I P a p i l i o ) E x p e r l e n t i a . 33. (1) 98 -

S t r a u s f e l d , N.J . (1976) At la s of an i n s e c t b r a i n . In Neural

p r i n c i p l e s i n v i s i o n - Edited by F. Z e t t l e r and

R. Weiles 245-279.

Spr inger B e r l i n , Heidelberg and New York.

S i e g l e r , M.V.S,, Burrows, M, (1979) . The morphology of l o c a l

non sp ik ing i n t e r neurones i n t h e me ta tho rac i c

gangl ia of t h e l o c u s t .

J . Comp. N e u r o l . . iS l» 121-148.

Trehe rne , J . E . (1965a) . The chemical environment of t h e

i n s e c t CNS i n Treherne J . E . and Beamort J . W.L.

( e d s . ) The phys io logy of t h e i n s e c t CNS.

Acad. P r e s s . London.

Treherne , J . E . (1966) . The NeurochOTiistry of a r t h r o p o d s .

Cambridge U n i v e r s i t y P r e s s .

- 4 1 -

Takeda, N., Ogura, N. (1976). induction of egg diapause by

implantat ion of Corpora cardiaca and corpora

a l l a t a i n Bombvx mqyl,.

J . Insec t . Phvs io l . . j ^ t 941-944.

Takeda, N. (1977b). A new neurosecretory pathway found in

the pars i n t e r c e r e b r a l i s of Monema flavescens

(Lept Heterogeneidae).

ADD. Snt. Zool . . 1 1 : i n Press .

Truman, J . W., Taghert, P, H. (1983). Insec t Neuropeptides, In

D. Krieger, M.J. Brownstein and J . Martin (eds.)

Brain Peptides. N

New York, Wiley & Sons P t 165-182.

*Vialanes, H. (1884). Etudes his tologiques et organologiques

sur l e s centres nerveux et l e s organs des sens des

animaux aa&ticules. Deuxiene memoire, Le ganglion

optique de la l i b e l l u l e (Aeschna maculatissima).

Ann, ggl. Nat, (ZQQI)* la: i-34.

*Vialanes, M.H. (1886-87). Recherches Sur I ' i h i s t o l o g i e des

i n s e c t s e t sur l e s phenomenes his tologiques qui

accompagnent l e developpment post-embryonnaire

des l e s animaux,

Ann. Sci . Nat. Se r . , 6 (Zool) H, Art. l i 1-348.

- 4 2 -

Van Der Kloot, W.G. {i960). Neurosecretion in i n s e c t s ,

Ann. Rev. Ent. t ^ : 35-52.

*Weber, H. (1933). Lehruch der Entomologie

G, Fischer, Hena.

Williams, CM. (1947). Physiology of in sec t diapause IV.

The bra in and prx)thoracic glands as an endocrine

system i n the Cegyopj^ silkworm.

BJLoI. g u i l t nafi frAQlt la^t V̂ Q<as Hpi^;

103 X 120-38 (Memoirs of Soc. of Endocrinology

PI 13 4) .

Williams, CM. (1948). Physiology of the insec t diapause I I I .

The prothoracic gland in the Cecrppi^ silkworm,

with special reference to t h e i r s ignif icance in

the aiibryonic and post embryonic developnent.

Biol . Byl l , 211 60-65.

Wlgglesworth, V.B. (1955a). Breakdown of the thoracic gland in

the adult i n sec t Rhodnius p ro l ixus .

J . E«P. PXQI' lit 485-497.

Wlgglesworth, V.B. (1955b). The ro le of haemocytes in the

growth and moulting of an i n s e c t . Rhodnius

prol ixus (Hemiptera).

J . EXP, b i o l . U * 649-663.

- 4 3 -

Wigglesworth, V.B. (1959) . The h i s t o l o g y of t h e nervous

system of an I n s e c t Rhodnlus p r o l i x u s (Hemip) l i .

The Cen t r a l gang l i a

Quar t . J . micr . S c i . . XQQ^t 299-315.

Wigglesworth, V.B. ( I 9 6 0 ) , The n u t r i t i o n of t h e Cen t ra l System

i n t h e Cockroach. F?ffAPlan?ta, americana L. The r o l e

of per ineur ium and g l i a l c e l l s i n t h e m o b i l i z a t i o n

of r e s e r v e s .

J . EXP. Biolf S j t 500-512.

Walker, R . J , , Grossman, A. R., Vfoodruff, G. N. , Kerkut , G.A. (1971)

The e f f e c t of b i c u c u l l i n e on t h e Gamma aminobutyric

acid (GABA) r e c e p t o r s of ndurones of P e r i p l a n e t a

americana and Hel ix flgpersg.

Brain Rest 33.1 75-82.

Wigglesworth, U.B. (1972) . The p r i n c i p l e s of i n s e c t physio logy

London Chapman & Hal l P. 75,

Weinbormair, G., Phlhammer, K,, Dumberger , H, (1977) . The

axon system of t h e ven t ro median p a i r of neuro­

s e c r e t o r y c e l l s i n t h e suboesophageal gangl ion of

Teleo a r v l l u s coimfnondus. Walkerx demons t ra t ion i n

whole mount p r e p a r a t i o n s by means of Reso rc in -

fuchs in . ( o r t h - g r y l l i e d a e ) .

- 4 4 -

MlcroscoDlc. 31 (5-6) 147-154.

Zool. I n s t , Univ. Akademlestr, 26j

A-5020 Salburg Austr ia .

•Zawarzin, A.R. (1924a). Uber der h i s to logische Beschaffenheit

des unpaaren ventralen Nerva der Insekten (Histo­

logische studien Uber Insekten 5) .

2. td-ss. Zool . , 122 (1) 97-115.

*Zawarzin, A.R, (19 24b), Histologische studien uber Insekten

6. Zur Morphologie der Nervenzentren Das Bauchmark

der Insekten, Ein Beitrag zur Vergleichenden

His tologie .

Z. Miss. Zool . , i i2 . (3 -4) , 323-424,

* = not seen in o r i g i n a l .

FIGURES

F ig , (1) Bra in of Danaus ch rvs ippus showing v a r i o u s

p a r t s : Pars i n t e r c e r e b r a i l s ( P i ) , Calyces

(Cy), S t a l k ( s ) . Corpora ped iuncu la t a (Cp).

F i g . (2) L a t e r a l s e c t i o n of t h e b r a i n .

2-6IJ

l-Bid

Fig, (3) Brain and the op t i c ganglion

connective (Cons),

Pig, (4) Optic ganglion with d i s t i n c t laminal

regions as seen under the l i g h t microscope,

j Brain (Br) , op t i c lobe (Opl) lamina (L),

medulla (M),

Fig-3

Fig.4

Fig, (5) Frontal sect ion of the thorac ic

ganglion with meso- and metathoracic

ganglion, Meso-thoracic ganglion (mes),

meta- thoracic ganglion (met), i n t e r -

ganglionic connective (Igc)

Fig. (6) Longitudinal sect ion of the f i r s t

thorac ic ganglion.

r 9

L

" " • " ^ ^ ^

;f m e s 'M

• • ' 1 . . « . • • , " ; — - •

k • ^ ' • ' ^ • • v ' ."*:

met ». /

J Fig.5

Flg-6

Pig. (7) Longitudinal section of the two

thoracic ganglia showing connection

with each other.

Pig. (8) Frontal view of metathoracic

ganglion (met).

Fig.7

Fig.8

Fig, (9) Longitudinal section of the thoracic

ganglion under higher magnification.

Fig, (10) Longitudinal section of first thoracic

ganglion showing neuromeres (Nm)

Fig.9

Fig 10

Pig. (11) Longitudinal sect ion of the raeso-

and raeta- thorac ic ganglion showing

ganglionic core .

Pig. (12) Frontal sect ion of meso- and meta-

thorac ic ganglia i n high magnification.

Fig.n

Fig.12

Pig. (13) Longitudinal section of the third

abdominal ganglion with neurilenuna

(Nlrn) and ganglionic core (gc)

Fig, (14) Longitudinal sections of third abdominal

ganglion in high magnification.

Fig-13

• : ^ -

FigU

Fig, (15) Diagram of the Central Nervous System showing

protocerebrum (Pr ) , deutocerebrum (dc),

t r i tocerebrum ( t r ) , thoracic ganglion (Tg)

abdominal ganglion (abd, gng. ) . Pars i n t e r -

ce rebra t i s ( P i ) , Optic nerve (Opt, ne r ) ,

antennal lobe (Ant, l ob ) , suboesophageal

ganglion (S .O.g , ) , Prothoracic ganglion

(Pro, gng.) 1st thorac ic ganglion (1 Tho,

gng), second thorac ic ganglion (2,Tho,gng),

th i rd thorac ic ganglion 3 , Tho gng)

th i rd ganglion (3rd Gng), fourth ganglion

(4th gng), f i f t h ganglion (5th Gng),

abdominal sp i racu la r nerve (abd. Spir , ner)

s ixth ganglion (6th Gang,), Genital chamber

(Gen. Cha). respec t ive ly .

Pa<S lA^.

roto. cer. to-cer.

3 rd Gng.

Ath Gng.

5th Gng.

obd. spir.ner.

Bth. Gng.

F'gis

%,

Fig. (16) Photomicrograph of the Central Nervous

systan showing Brain (Br,), thoracic

ganglion (Tg) and abdominal ganglion

(abd. gng).

Pig. (17) Abdominal ganglia with prominent

nerves.

Fig-ie

Fig.17

Fig. (18) Transverse section of abdominal

ganglia - Ganglionic core (gc).

Pig. (19) Photomicrograph of second abdominal

gangl ion ' I l n d abd, gng) .

Fig-18

Fig.19

Fig, (20) Thoracic gangl ion with ne rves . Thoracic

connec t ive (Tho, Con), P ro tho rac i c gangl ion

( P r o t . Gng), P r o t h o r a c i c connec t ive

( P r o t . Con), Mesothoracic ganglion (Meso.

Gng), Meta thorac ic gangl ion (Meta Gng.) L

L a t e r a l nerve (Lat , ner) v e n t r a l neirve Cord

(V.N.C. ) .

F ig , (21) Diagram showing t h e l a s t abdominal

gangl ion . Vent ra l nerve cord (V, N, c ) .

S ix th gangl ion (Vl th gng) nerve of

e x t e r n a l gangl ion (ne r , ex t . gng).

Tho.Con.

Prot.Gng.

Prot.Con.

Meso.Gong.

Meta.Gng.

FJ9.2O

V.N.C

Vlthgng.

ner. ext. gng.

Fi9-2I