THE ADKENAL BODIES 99 



logical and chemical tests, and from careful histological 

 comparisons. 



The paired "suprarenal bodies" (chromaphil) are situated 

 on branches of the aorta, segmentally arranged, and extend 

 on each side of the vertebral column from the front part of the 

 sinus of Monro to the posterior end of the kidney. The anterior 

 pair are elongated, and correspond usually to three or four 

 segments. These bodies are in close relation to the ganglia 

 of the sympathetic chain, and contain large numbers of chroma- 

 phil cells, though they appear not to be made up entirely of 

 them. (Figs. 14, 15 and 22.) 



The inter-renal body [Figs. 14 and 15 (i.r.)] is an " ochre- 

 yellow " rod-shaped structure, paired in the rays, unpaired in 

 the dogfishes and sharks, lying usually in the region of the 

 posterior part of the kidney, but sometimes extending as far 

 forward as the anterior extremity. It bears a striking resem- 

 blance in its colour, general appearance, and relations to the 

 kidney, to the adrenals of the Anura, and in the first two of 

 these features to those of the Reptilia. The body consists of 

 cells which have the same general appearance and the same 

 micro-chemical reaction as the " corpuscles of Stannius " (the 

 cortical adrenals of Teleostean fishes), and the cortex of the 

 adrenals of higher vertebrates. (See Fig. 21.) 



The effect of injection into the venous system of a mammal 

 extract made from the " paired bodies " of Elasmobranchs is 

 shown in Fig. 16. It will be seen that there is a very marked 

 rise of the arterial blood-pressure. In Fig. 17 is seen the effect 

 of the injection of an extract made from the inter-renal. There 

 is a certain effect upon the blood-pressure which can be readily 

 explained as the result of more or less admixture with " medul- 

 lary glands " in making the extract. 



In Teleosts the cortical adrenal bodies are usually paired, 

 round or oval, pale pink bodies, placed on the spinal or ventral 

 surface of the kidney. They are near the posterior extremity 

 of the renal mass, and are either free on its surface or more or 

 less embedded in its substance (Figs. 18-20). The constituent 

 cells are of the same character, and have the same arrangement 

 as those of the inter-renal of Elasmobranchs (Figs. 23, 24) It 

 is now fully ascertained that these structures (the " corpuscles 

 of Stannius ") in Teleosts represent the inter-renal of Elasmo- 

 branchs. It had been erroneously considered by some authors 



