THE PHYLA HEMICHORDATA AND CHORDATA 



Fig. 18.14. Representative modern Caudata, or tailed amphibians. A, Ambystoma tigruumi, the 

 axoiotl, a permanently aquatic salamander with persistent external gills. B, the Congo snake, 

 Amphmma, with very small limbs. C, the hellbender, Cryptohranchus, here shown with a mass 

 of developing embryos. (All photographs courtesy New York Zoological Society.) 



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