THE PITUITARY 367 



hyaline, or colloid bodies become very numerous ; they appear 

 to be partly of a cellular nature and to find their way between 

 the ependyma cells into the infundibular recess and ventricles 

 of the brain. The colloid appears to arise from the epithelial 

 cells of the pars intermedia. 



The precise nature of the relationship existing between the 

 thyroid apparatus and the pituitary body is by no means clear. 

 Simpson and Hunter report that complete removal of the 

 thyroid gland in lambs does not lead to the appearance of 

 iodine in the pituitary. On the assumption that the iodine 

 containing substance of the thyroid represents its active 

 secretion, this does not support the Rogowitsch theory that, in 

 thyroid insufficiency, the pituitary vicariously takes on its 

 function. In the experiments of Simpson and Hunter, there 

 was, however, some compensatory hypertrophy of the pituitary 

 body. 



It only remains to make reference to some experiments of 

 Masay in opotherapy, with the object of ascertaining whether 

 pituitary extract can replace the internal secretion of the 

 thyroid ; the results were entirely negative. 



K. Pituitary Insufficiency and a Pituitary Antiserum 



or Cytotoxin 



Masay has attempted to produce pituitary insufficiency by 

 the method employed by Demoor and Van Lint in order to 

 obtain an " anti-thyroid serum." Guinea-pigs were injected 

 intraperitoneally with an emulsion of dog's pituitary at intervals 

 of two days. After three, four, or five injections the blood of 

 the guinea-pig was collected and centrifugalized, and the serum 

 (about 10 c.c.) was injected under the skin of a dog. Masay 

 gives his results in considerable detail, and the effects upon the 

 animal are shown in a series of illustrations. After a certain 

 number, usually two or three, of such injections the dogs show 

 symptoms, such as loss of flesh, muscular weakness, especially 

 in the hind limbs, changes in the skeleton and in the structure 

 of the pituitary, the symptoms constituting, according to 

 Masay, a veritable cachexia hypophyseopriva. 



Ossokin reports that the " hypophyseolytic serum," prepared 

 from the blood of dogs immunized with posterior lobe of 



