U. S. B. F.— Dr 



PLATE XXI. 



FIGS. 1 TO 8.— TRANSFORMATION SIZES. NATURAL SIZES. 



illfrog; 2, green frog; 3, pickerel fro?: 4, leopard frog; 5, tree toad; 6, wood frog 

 7, peeper; 8, common toad. (After Wright, Carnegie Pub!. No. 197.) 



