290 



ZOOLOGY 



SECT. 



Segmentation is unequal and usually incomplete. But in Pipa, 

 Alytes, and a Coecilian belonging to the genus Epicrium there is 



FIG. l03. A, early. B, advanced. Larva of Epicrium giutinosum, with external gills. 



(From "Wiedersheim, after Sarasin.) 



a large quantity of food-yolk over which the developing embryo 

 lies coiled very much as in the Trout (Fig. 903, A). 



Distribution. The Urodela are almost exclusively PalaBarctic 

 and Nearctic forms, occurring in North America, Europe, Asia, and 



]MI.;. '.'04. Amblystoma tigrinum. Larval or Axolotl stage. (From ilivart.) 



North Africa : a few species extend southwards into the Neotropical 

 and Oriental regions. The Gymnophiona, on the other hand, are 

 mainly southern, occurring in the Neotropical, Ethiopian, and 



