122 Blair Bell 



Silbermark (11)10 (IS)), in the reference given by Biedl (with whom 

 he worked), discusses the technique of the operation. Apparently the 

 results he obtained with Biedl are only recorded, without details, in 

 Biedl's work. 



The results of my experiments do not entirely confirm the work of 

 Gushing and his associates, which is undoubtedly the most reliable and 

 satisfactory of all the experimental work carried out on the subject. It 

 will therefore be of interest to discuss the points of confirmation and con- 

 tradiction, and to find, if possible, some explanation of the ditierences. 

 Although I am far from convinced by the evidence of the small series 

 of operations recorded here that the results obtained will stand the test 

 of further research, nevertheless they appear to fit in with the most reason- 

 able explanation of pituitary activity, as I shall explain directly. 



The results of my experiments concerning the efiects of total extirpation 

 of the pituitary, and of the removal of very large portions of the pars 

 anterior, confirm the statements of Paulesco and Gushing that such 

 procedures are fatal. 



Sweet and Allen (1918 (19)) alone of recent investigators deny that 

 the pituitary is essential to life ; but it appears to me that their technique 

 is open to criticism. 



My experiments also confirm the fact demonstrated bj^ Paulesco and 

 Gushing that the removal of the pars posterior produces no symptom. 

 Further, I have been able, by means of the control specimens removed 

 before the operation on the pituitary, to show that the genitalia not only 

 do not undergo atrophy, but continue to develop in the young female after 

 removal of this portion of the pituitary. 



With regard to the points wherein my experiments produced results 

 difierent from those obtained by Paulesco, Gushing, and others, the most 

 striking is undoubtedly in connexion with the production of dystrophia 

 adiposo-genitalis. Whereas Gushing — and probably Paulesco, although 

 he failed to recognise the importance of the condition — found that partial 

 removal of the pars anterior was the lesion responsible for this syndrome, 

 in none of the cases in which I removed portions of the pars anterior did 

 dystrophia adiposo-genitalis supervene, although when sufl[icient was 

 removed, and there was a considerable lapse of time between the operation 

 and death, genital atrophy was usually found. In one case there was an 

 actual loss of weight in a young animal in 210 days. This animal remained 

 stunted. In other cases the animals increased in size. 



I found, however, that the syndrome dystrophia adiposo-genitalis 

 followed clamping and separation of the infundibular stalk. In two out 

 of three cases there was atrophy of the genitalia, with considerable adi- 

 posity ; in one case the increase amounted to Q6 per cent, of the body weight 

 in 51 days. 



It is not impossible to reconcile these diverse findings, especially if we 

 study the difficulties Gushing encountered when he attempted to make 



