444 



Comparative Morphology of Chordates 



Fig. 342. Diagram of the relations of external and 

 internal gills in the anuran tadpole, (ab, eb) Afferent and 

 efferent branchial arteries; (h) heart; (o) ear cavity; (ph) 

 pharynx; (ra) radix aortae. (After Maurer. Courtesy, 

 Kingsley: "Comparative Anatomy of Vertebrates," 

 Philadelphia, The Blakiston Company.) 



W^ 



w 



Fig. 343. Tadpoles. (A) liana alticola. (B) Microphyla heyrnonsi. (C) Gastro- 

 phryne carolinensis. The shape of the mouth may be correlated either with the type 

 of habitat or with the method of feeding. The umbrella mouth (B) characterizes 

 surface-film feeders. Some species, notably the Brevicipitidae (C), show very 

 little specialization of the mouth in spite of radically different feeding habits. (By 

 permission from "Biology of the Amphibia," by G. K. Noble, copyrighted 1931. 

 McGraw-Hill Book Co., Inc.) 



