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Mouth-Parts of Mature Tadpoles. X15. 



1. Rana catesbeiana. 5. Rana sylvatica. 



2. Rana palustris. 6. Bufo lentiginosiisamericanus. 



3. Rana pipiens. 7. Hj^a pickeringii. 



4. Rana clamata. 8. Hyla versicolor. 



