422 Animal Biology 



for sensory purposes and (2) the stratum compactum consisting of dense 

 connective tissues in which the fibers run somewhat parallel to the sur- 

 face of the skin and among which are blood vessels. The smooth, scale- 

 less, hairless skin functions as an organ of respiration as well as gives pro- 



STRATUM CORNEUM ^^ 



MALPIGHIAN LAYER ^'f 



fPIGMENT BODIES jjf' 



MUCOUS GLAND 



STRATUM SPONGIOSUM - 



POISON GLAND 



2 

 K 

 bJ 



a 



2 

 3 



i 



o 



STRATUM COMPACTUM 

 BLOOD VESSELS 



Fig. 208. — Skin of frog (cross section and somewhat diagrammatic). Com- 

 pare this with human skin (Fig. 228). (From Parker and Clarke: An Introduc- 

 tion to Animal Biology, The C. V. Mosby Co.) 



^a-^rf/ 



A 



Fig. 209. — Pigment melanophore from the frog (Rana temporia) . A, Pig- 

 ment distributed in response to Hght; B, pigment contracted. (From Potter: 

 Textbook of Zoology, The C. V. Mosby Co.; redrawn and modified from Noble: 

 Amphibia of North America, McGraw-Hill Book Co., Inc.) 



