16 ANATOMY 



phil tissue within the rim of cortical cells as observed in the 

 mammal. In Urodela the adrenal occurs as a series of strips 

 which extend along the kidney and project anteriorly as far 

 as the origin of the subclavian artery. 700 



An intimate relation between the chromaphil and interrenal 

 tissues is first encountered in the reptilian adrenal. Here we 

 find the relation of these tissues to vary from that described 

 above for the amphibia to the condition met with in the bird 

 and described in the next paragraph. Thus in the crocodiles 

 and sea turtles (Chelonia) the arrangement is practically iden- 

 tical with that seen in the bird while in the tortoise (Testudina) 

 the arrangement occurring in the frog is encountered. 498 - 608 



In the birds the adrenals consist of ochre colored bodies 

 situated on each side of the vena cava. The left gland is 

 usually lenticular in shape with its internal border excavated 

 and molded around the vena cava or abdominal aorta. The 

 right gland is pyramidal in shape and also in intimate contact 

 with the vena cava. The adrenals in the bird lie at the anterior 

 end of the kidney in intimate contact with the reproductive 

 organs. Microscopically, the adrenals in the bird consist of an 

 interlacement of the interrenal and cortical tissues. Each 

 occurs in the form of strands of cells which intertwine with one 

 another. These strands have been designated as "chief" 

 and "intermediate" strands to denote the interrenal and 

 chromaphil tissues, respectively. 



It is only in the mammals that we find the interrenal tissue 

 as a cortex surrounding a medulla composed of chromaphil 

 tissue. The cortex is the homologue of the cortical or inter- 

 renal columns of the reptile, bird, and amphibia, of the cor- 

 puscles of Stannius in the Teleosts, and of the interrenal body 

 in the Elasmobranch fishes. The right adrenal in the mammal 

 is situated in close contact with the vena cava. It is usually in 

 close apposition to the kidney but in some species it may be 

 separated from and situated a short distance anteriorly to the 

 kidney. The left adrenal is, in most species, situated away 



