150 CORTEX 



animals do not survive the operation well during the summer, 

 when they die within one to three days, but during the winter 

 months the animals survive for one to three weeks if maintained 

 at a low temperature. 300 This seasonal variation is also ob- 

 served in other cold blooded animals. One might expect that 

 the depressed metabolism of hibernating periods would lead 

 to less rapid deterioration of the organism than during the 

 period of bodily activity. The survival period is markedly 

 shortened if the poikilothermic animal is subjected to an ele- 

 vated external temperature. 



Adrenalectomy in frogs leads to a train of symptoms similar 

 to those observed in the mammal. The animals in in- 

 sufficiency are easily fatigued. There is incoordination and 

 weakness of the hind legs and paresis involving first the flexor 

 and adductor and finally the extensor muscles. Eventually 

 the fore limbs are also affected. Death is preceded by marked 

 edema, which is to be attributed probably to renal injury since 

 the close apposition of the adrenals to the kidneys renders 

 adrenalectomy without serious renal injury virtually im- 

 possible. 



Abelous and Langlois 3 noted that the length of survival of 

 their frogs was inversely proportional to the intensity of 

 their metabolism. Exercise, for example, hastened the onset 

 of the final stages of insufficiency. These authors also experi- 

 mented with some success on the prolongation of life by the use 

 of grafts 4 and by the use of saline extracts of adrenal glands. 

 They found the blood of their animals dying of insufficiency 

 to manifest toxicity when injected into normal animals. 6 



Adrenalectomy in frogs is best performed through a lumbo- 

 dorsal incision. A fine cautery is used to destroy the glands. 

 Since no capsule separates the adrenal from the kidney one can 

 not avoid injuring the latter organ. 



Birds. Adrenalectomy in birds was first performed by 

 Gourfein 235 in 1896. He found the operation in pigeons to be 

 fatal within 4 to 24 hours. If one-eighth to one-tenth of one 



