THE PITUITARY BODY 



behavior changes. Only sheep pituitary extract caused, in 

 addition to these changes, maturation of ova or ovulation 

 and oviposition. MelHsh (1936) investigated pituitary-gonad 

 interrelationships in the horned lizard, Phrynosoma cornutum. 

 Prolonged illumination of animals furnished abundant food 

 and kept at a high temperature (35° C.) for six weeks during 

 winter had little effect on the gonads (control lizards hiber- 

 nating at 5° C). On the other hand, if the experimental ani- 

 mals were also given the equivalent of 3 gm. of whole pitui- 

 tary of the pig, the gonads of both sexes were stimulated so 

 as to resemble those of animals early in the breeding season. 

 Other experiments in similar lizards have been reported by 

 Mellish and Meyer (1937). hw increased ovarian weight, 

 largely due to an increased deposition of yolk, was produced 

 by the administration of various anterior pituitary extracts 

 or pregnant-mare serum. The animals were well fed and 

 kept at 32° C. under continuous artificial illumination. None 

 of the animals was hypophysectomized. An unfractionated 

 anterior pituitary extract did not affect the ovaries of ani- 

 mals hibernating at 5° C. At that temperature there ap- 

 peared to be only partial absorption of the extract. 



Forbes (1937) investigated the action of an alkaline extract 

 of whole pituitary of sheep in immature alligators (4-18 

 months after hatching). Some hypertophy of the ovaries to- 

 gether with marked growth of the oviducts occurred in fe- 

 male animals. There was no effect on the Wolffian ducts. In 

 males a marked hypertrophy of the testes, without sperma- 

 togenesis, was produced. The size of the mesonephron in 

 males receiving the extract was reduced. 



Birds. — In the past few years there has been reported a 

 considerable number of new or more detailed observations 

 on the physiology of gonadotropic hormones in birds. Almost 

 all deal with hormones of pituitary origin.'' An interesting as- 



* Later reports also support the conclusion that prolan has no significant effect 

 on the gonads of birds (Hill and Parkes, 1935; Witschi and Keck, 1935; Uhl and 

 others, 1937). Breneman's results (1936) apparently were inconclusive. Koch 

 (1935) could not confirm his earlier report that prolan brings about an increase in 

 the egg-laying performances of hens. 



