346 THE PHYSIOLOGY OF REPRODUCTION 



of male secondary characters by a cow previously normal after cystic 

 degeneration of the ovaries. Since in this case the interstitial 

 secreting mechanism of the ovaries was normal, it is suggested that 

 the full development of secondary female characters is correlated with 

 the corpus luteum. 



Steinach has carried out a number of experiments on rats and 

 guinea-pigs, producing the converse effect to that described above. 1 

 After transplanting the ovary into previously castrated males when 



FIG. 89. Ovariotomised Rouen duck Type II. 

 (From Goodale.) 



(Cf. Figs. 86, 87, and 88.) The bird was operated upon 

 when about a year old. 



they were young, very definitely female characters have developed. 

 Most noteworthy was the growth of the mammary glands and teats, 

 a feminised male guinea-pig yielding milk and suckling young ones. 

 Moreover, the hair is said to have resembled that of the normal 

 female, being finer and softer than in the normal male, and the size 

 of the body was reduced. Lastly, the feminised animal reacted 

 sexually like a female as shown especially by the " tail erect " reflex 

 (normally concerned in coition) and the " kick guarding " reflex (used 

 to keep off the male before the onset of oastrus). The follicles in the 

 transplanted ovaries atrophied, but the interstitial cells (or " theca 

 lutein " cells) remained, and these Steinach regards as representing 



1 Page 331. 



