HYPOPHYSIS CEREBRI 321 



animals ; there was a shortening of the skull and especially of 

 the muzzle, hypoplasia of the genitals, anomaly in the growth of 

 the hair, considerable deposition of fat, even fatty degeneration 

 of the internal organs (liver), and temperamental changes. The 

 dogs ceased to bark, they breathed heavily, they became somewhat 

 apathetic, the sensibility to electric stimulus and to pain became 

 very much less, while their movements were indolent, and they 

 seemed to have become less intelligent. In male animals, sperma- 

 togenesis ceased, in female animals there was involution of the 

 ovarian follicles. 



A glance at the material provided by experimental extirpation 

 of the hypophysis shows that a good deal of light has been shed 

 upon the functional and physiological significance of that organ. 

 It is evident, in the first place, that the hypophysis is an organ of 

 vital importance to the organism, the removal of which is 

 followed by death. This is conclusively proved by the results of 

 Paulesco's method of complete hypophysectomy, the contradictory 

 results obtained by certain investigators being probably attribut- 

 able to the faulty nature of their technique. " Total hypo- 

 physectomy " can only be described as such where, in addition 

 to the removal of both lobes, the hypophysal peduncle is also 

 severed. The peculiar significance of this peduncle is shown by 

 the fact that, even where the hypophysis is allowed to remain 

 in situ, death follows resection of the peduncle as promptly as after 

 complete hypophysectomy. This remarkable phenomenon was 

 first observed by Paulesco, and has since been confirmed by me; 

 all that we can do is to record the facts, for no explanation of 

 them is at present forthcoming. 



The results of experimental extirpation also show the differ- 

 ence in the physiological value of the two lobes of the hypophysis. 

 The removal of the posterior lobe is unattended, over a period of 

 months, by pathological signs. Total extirpation of the anterior 

 lobe, on the contrary, is immediately fatal. It appears, however, 

 that this applies only to older animals, young dogs having a 

 longer duration of life. 



The results of total or partial destruction of the anterior lobe 

 are also best seen in young animals. The suppression of function 

 is manifested in a considerable increase in the fat body, which 

 may amount to adiposis universalis, with pronounced hypoplasia 

 of the sexual glands, together with arrested development and 

 infantile habit. The influence which the hypophysis has upon 

 the sexual glands is seen also in the case of older animals, partial 

 destruction of the anterior lobe being followed by marked atrophy 

 of the genitals. 



PITUITARY EXTRACT. 



Since the discovery by Oliver and Schafer of the vaso-con- 

 tractor action of pituitary extract, the symptoms which follow the 

 21 



