U. S. B. F. — Doc. 



PLATE XX. 



FIGS. 1 TO n.— MATURE TADPOLES, NATURAL SIZES. 



1 2-vear-old bullfrog tadpole; 2, 3 to 5 months old bullfrog tadpole; 3, 1-year-old bull- 

 frog tadpole; 4, leopard-frog tadpole; 5, 1 -year-old green-frog tadpole; 6, pickerel-frog 

 tadpole: 7, 3 to 6 months old green-frog tadpole; 8, tree-toad tadpole; 9 Peeper tadpole. 

 10 wood-frog tadpole; 11, common toad tadpole. (After Wnght, Carnegie Publ. No. 197.) 



