PHYSIOLOGY AND EXPERIMENTAL PATHOLOGY 105 



the interrenal tissue had been completely extirpated died with char- 

 acteristic symptoms. 



Although the results of Pettit and of Vincent (&) (c) on the Teleosts did 

 not agree with those of Biedl, this was later accounted for by Giaco- 

 mini's discovery, that in the eel, in addition to the body of Stannius and 

 neighboring interrenal tissue, there is found an anterior cranial mass of 

 interrenal tissue. This had been overlooked by Vincent. 



In mammals Biedl(#) claims that he was able to remove the cortex, 

 leaving the medulla intact. Death followed. Such an operation appears 

 little better than removal of the whole gland because of the intimate vas- 

 cular connection between cortex and medulla. However, because of the 

 results with fish we may conclude that the cortex is essential for life. 



As regards the medulla the answer is more difficult, H. and A. Cris- 

 tiani(o-), in their attempts to determine the minimal suprarenal tissue 

 necessary for life, found from histological examination that only those ani- 

 mals survived which possessed a small portion of functioning medullarv 

 tissue. Small pieces with medullary substance permitted life while rela- 

 tively large pieces in good condition but without medullary substance were 

 not sufficient to preserve life. 



But more recently Wheeler and Vincent have destroyed all of the 

 medullary tissue in the two glands by removal of one ; amputation of 

 half of the other and cauterization of the medulla in the remaining half. 

 They state that in several instances where the whole or practically the 

 whole of the medulla has been destroyed the animal has survived without 

 symptoms. The animals were kept for three or four weeks, the gland tis- 

 sue being examined microscopically for medullary tissue at the conclusion 

 of the experiment. This work indicates that the medulla is not essential 

 or at least from all of the evidence available we may conclude that of 

 the two tissues the cortex is the more important. Extrasuprarenal chroma- 

 phil tissue might function sufficiently to replace the loss of medullary 

 tissue; but even so, it follows that the medullary tissue is not essential 

 to life. 



Symptoms of Suprarenal Insufficiency. The syndrome of experi- 

 mental suprarenal insufficiency develops rapidly in a large proportion of 

 the cases. Usually the first severe symptoms occur only a few hours be- 

 fore death. Therefore it is not surprising that the picture is not identical 

 with that of Addison's disease, which is due no doubt to slowly developed 

 suprarenal insufficiency. 



Of the very many accounts of the general symptoms following epine- 

 phrectomy that of Elliott (/) is one of the best. His experiments were 

 made on the cat. In a series of 21 animals,, both glands were removed 

 at the same operation, nineteen dying within 48 hours. In another series 

 of twenty-five cats the glands were removed in two stages, three weeks 

 to nine months apart. Survival in this series ranged from six to twenty- 



