Comparative Chemistry of the Suprarenal Capsules, fyc. 353 



bodies ("corpuscles of Stannius ") of Teleosts do not contain the 

 physiologically active principle which is characteristic of suprarenal 

 medulla. This is shown both by testing the action of an extract 

 made from them upon the blood-pressure of a living mammal, and 

 also by the effects of subcutaneous injection of an extract.* In both 

 cases negative results are obtained. 



The natural conclusion to be drawn from these observations would 

 seem to be that the representative of the suprarenal medulla is absent 

 in Teleostean fishes. But that an organ of such manifest and vital 

 importance in mammalsf should be totally unrepresented in by far 

 the majority of living fishes, seemed to us so remarkable that we con- 

 sidered it necessary to furnish some further evidence upon this point. 



In our previous paper upon the comparative chemistry of the 

 suprarenal capsules, J we had to regret that material for investigation 

 of the chemistry in Teleosts had been wanting. Since then, how- 

 ever, we have obtained six large specimens of Gadus morrhua. The 

 suprarenal bodies obtained from these weighed in a moist state 

 0*42 gram. These were boiled with normal saline so as to make a 

 10 per cent, decoction ; this was carefully filtered and the pale yellow 

 filtrate tested for the chromogen with chromic acid, ferric chloride, 

 &c, as described in our previous paper, but no colour reactions what- 

 ever were obtained. The same experiment was tried with material 

 from Anguilla anguilla. As some observers § have believed the 

 lymphoid " head -kidney " to have something to do with the supra- 

 renal bodies, we have tested this also for the chromogen, with entirely 

 negative results. || 



Again, we have examined other portions of the kidney with the 

 greatest minuteness, but have failed to find anything which resembled 

 the suprarenal medulla, either in its histological, physiological, or 

 chemical features. 



The chief facts in our possession are, then, as follows : — 



1. The known suprarenal bodies of Teleosts resemble anatomically 

 and histologically the inter-renal body of Elasmobranchs and the 

 cortical portion of the suprarenal capsules of higher vertebrates. 



2. An extract made from them, when injected into the blood-vessels 

 oi a living mammal, does not raise the blood-pressure. 



3. The extract does not produce physiological effects w T hen injected 

 subcutaneously. 



* Swale Vincent, loe. cit. 



f See Oliver and Sckafer, 'Journ. of Physiol./ vol. 18, No. 3, 1895. 

 J c Eoy. Soc. Proc.,' read December 11, 1897. 



§ ' Weldon, ' Quart. Journ. Mic. Soc.,' toI. 24, p. 171, and vol. 25, p. 127; also 

 G-rosglik, ' Zool. Anz.,' 1885. 



|| It has been previously determined that "head-kidney" contains no physio- 

 logically active substance. 



