div class=trans-pagebuttonPage 1button div class=trans-image amp-img class=trans-thumb alt=Page 1: Chromosomes of South American Amphibians src=https:reader030fdocumentsusreader030viewer2022020522575068141a28ab0f07ae8249html5thumbnails1jpg width=142 height=106 layout=responsive amp-img divp© 1960 Nature Publishing Grouppdiv