92 THE SEX-COMPLEX 



development of the breasts as an important sex-char- 

 acteristic, but that subsequently the functions of the 

 ovarian secretion are not specially or directly related to 

 mammary activity. 



Effect of Xhe pituitary and the mammae. — Crowe, Cushing 



experimental r " 



lesions of the and Homans 1 have shown that the infantilism produced 

 the U mamm8e. DV the removal of a portion of the anterior lobe of the 

 pituitary includes an arrest in the development of the 

 mammae. In my own experiments on the pituitary 

 the mammas were found to be infantile in those cases in 

 which the genitalia showed retrogressive changes after 

 operation — that is to say, after removal of large portions 

 of the anterior lobe, and after the stalk had been clamped 

 or separated. 



Whether this mammary infantilism is secondary to 

 the ovarian hypoplasia which follows partial hypo- 

 physectomy, or is direct, we have no certain means of 

 knowing. It is obvious, of course, that the ovarian 

 hypoplasia, produced by pituitary lesions, might lead 

 to infantilism of the mammae, but it is quite impossible 

 with our present knowledge to say whether the pituitary 

 lesion itself directly affects the development of the 

 mammary glands. This point may some day be de- 

 cided by investigations on the state of these glands in 

 animals in which the pituitary has been subjected to 

 lesions during early pregnancy. It is well known that 

 there is increased activity in the anterior lobe during 

 pregnancy, and that the secretion so produced, like 

 that of the posterior lobe (infundibulin), influences the 

 retention of lime salts which are required for the foetus 

 and also for the secretion of milk. 



There is, moreover, another fact of importance in 

 this connexion. In 1910 Ott and Scott 2 observed that 

 the extract of the posterior lobe of the pituitary has a 



1 Crowe, S. J., H. Cushing, and J. Homans, Bull. Johns Hopk. Hosp. 

 1910, vol. xxi, p. 127. 



2 Ott, I., and J. C. Scott, Proc. Soc. Exper. Biol, 1910-11, vol. viii, 

 p. 48. 



