THE PITUITARY BODY 



pituitary in determining accurately qualitative and quantita- 

 tive effects of extracts. The increased accuracy of interpre- 

 tation more than justifies the great increase of labor required. 

 Final judgment on the effect(s) of an extract should be 

 based upon experiments with hypophysectomized animals. 



The follicle-stimulating hormone often excreted in human 

 urine in considerable amounts after spaying or castration or 

 after the menopause probably originates in the anterior pitui- 

 tary. On the other hand, the gonadotropic substances dis- 

 cussed in chapter iv appear not to be secreted by the hy- 

 pophysis. These substances are prolan (from the chorionic 

 cells of the human pregnant uterus), the gonadotropic hor- 

 mone characteristic of pregnant-mare serum (likewise prob- 

 ably secreted by chorionic orendometrial cells), and the gonad- 

 otropic hormones of neoplasms such as hydatidiform mole, 

 chorionepithelioma, and testicular tumor (from the cells of 

 the neoplasms). 



In this chapter a systematic account of pituitary-gonad 

 interrelationships, especially as these are understood from 

 later work, will be attempted. It is hoped that the reader will 

 recognize the diversity of the literature both in subject mat- 

 ter and in quality. Diversity in the former often makes ar- 

 rangement difficult. Diversity in the latter may lead to defi- 

 nite conclusions, either sound or wrong. Sometimes, however, 

 the only reasonable position to take is one of suspended 

 judgment, unwelcome as this may be to many readers. 



THE BIOLOGY OF THE GONADOTROPIC 

 HORMONES IN VERTEBRATES 



Fishes. — Using an extract of ox pituitary. Young and 

 Bellerby (1935) were unable to produce either significant 

 changes in the gonads or metamorphosis in the lamprey 

 {Lampetra planeri). However, changes in body-shape and 

 marked cloacal swelling, both secondary sexual characteris- 

 tics of the period preceding spawning, appeared. In earlier 

 reports several authors had succeeded in producing spawning 



[48] 



