LIST OF ILLUSTRATIONS Continued. 



PLATE IX Continued. 



FIG. 2. Relative sizes of transformed examples. XI. 



A. Rana catesbeiana. D. Rana pipiens. G. Hyla pickeringii. 



B. Rana clamata. E. Hyla versicolor. H. Bufo lentiginosus ameri- 



C. Rana palustris. F. Rana sylvatica. canus. 



PLATE X. Range of transformation-size. 



1. Bufo lentiginosus americanus. 4. Rana sylvatica. 7. Rana clamata. 



2. Hyla pickeringii. 5. Rana palustris. 8. Rana catesbeiana. 



3. Hyla versicolor. 6. Rana pipiens. 



PLATE XI. American toad (Bufo lentiginosus americanus). 



1. A female toad which was dug out of a sandy-loam b;mk, March 13, 1898. Wide 



awake when submitted to the temperature of a warm room. X0.75. 



2. The same toad resuming the hibernating attitude when placed out-of-doors in 



a temperature almost freezing. X0.75. Figs. 1 and 2 by S. H. Gage. 



3. A toad in its summer burrow. Photograph by A. A. Allen. 



4. A croaking male partly in the water. Flash-light. 



PLATE XII. American toad (Bufo lentiginosus americanus). 



1. Myriads of transformed toads on the shore of Beebe Lake, Ithaca, N. Y. 



2. Curled egg-strings. 



PLATE XIII. 



Peeper (Hyla pickeringii). 



1. A croaking male. Note mosquito on his leg. Flash-light. 



2. Same individual as in figure 1. Flash-light. 



3. An adult peeper. Note cross on the back. Photograph by C. R. Crosby. 



4. Mated pair. Axillary amplexation. XI. 5. 



5. A series of peepers from tadpole to transformed peeper. Dorsal aspect. XL 

 American toad (Bufo lentiginosus americanus). 



6. Mating mass of toads. Photograph by A. A. Allen. 



7. Series of toads from tadpole to transformed toad. Dorsal aspect. XL 



PLATE XIV. Tree-toad (Hyla versicolor). 



1. A typical place for the breeding of tree-toads. 



2. A male tree-toad croaking. Flash-light. 



3. A male tree-toad hit on the head by hot flash-light powder. 



4. Egg-packet of tree-toad eggs attached to Potamogeton leaves. 



5. A series of tree-toads from tadpole to transformed tree-toad. Dorsal aspect. XL 



PLATE XV. Leopard- or meadow-frog (Rana pipiens). 



1. An area of egg-masses. Fourteen masses in the illustration. 



2. A stick with three egg-masses, the two upper globular masses being of Rana 



palustris, the lower plinth-like mass, Rana pipiens. 



3. Meadow-frogs from tadpole to transformation. Dorsal aspect. XL 



PLATE XVI. Pickerel-frog (Rana palustris). 



1. An egg-area and one mated pair. 



2. A croaking male showing vocal sac on either side of the head. Flash-light. 



3. Pickerel-frogs from tadpole to transformation. Dorsal aspect. XL 



PLATE XVII. Green-frog (Rana clamata). 



1. Mated pair. Pectoral amplexation. 



2. Two detached portions of an egg-film. Wind or current often separates the 



one film into several. 



3. An egg-film (at surface) near the shore among grass. 



PLATE XVIII. Green-frog (Rana clamata). A series from first season's tadpole to trans- 

 formed green-frog. Dorsal aspect. XL 

 PLATE XIX. Bullfrog (Rana catesbeiana). A series from the first season's tadpole (three 



months old) to the transformed bullfrog. Dorsal aspect. XL 

 PLATE XX. 



1. Bullfrog (Rana catesbeiana). An egg-film, If feet in diameter. 



2. Wood-frog (Rana sylvatica). The egg-mass of the wood-frog compared with 



that of the leopard-frog (at right). 



PLATE XXI. Wood-frog (Rana sylvatica). 



1. An egg-area in a pond filled with dead sticks and leaves. 



2. An adult wood-frog. 



3. A series of wood-frogs from tadpole to transformed wood-frog. Dorsal 



aspect. XL 



TEXT-FIGURE 1. Individual eggs. X4. 



A. Bufo lentiginosus C. Hyla pickeringii. F. Rana catesbeiana. 



americanus. D. Rana clamata. G. Rana pipiens. 



B. Rana palustris. E. Hyla versicolor. H. Rana sylvatica. 



