no INTERNAL SECRETIONS OF THE OVARY 



claimed to have secured active extracts from the testis, but 

 Allen and his co-workers (21) failed to obtain this result. 



Hirsch (301) and Frank and Goldberger (228) obtained a 

 number of positive results from male blood. 



Table 7. — CEstrin in Post-Partum Urine. 



Several authors (162, 348, 422, 437) have reported the 

 preparation of oestrin from male urine. Loewe (422) even 

 states that oestrin can be fractionated from the male sex 

 hormone in the urine. It is certain that small amounts (1-3 

 m.u. per litre) of a substance which will cause cornification of the 

 vagina of the rat and mouse can be obtained from male urine, 

 but in view of recent doubts of the absolute specificity of this 

 test, it is necessary that every possible criterion of oestrus should 

 be used before the substance is definitely identified as oestrin 



(437)- 



Distribution in animals other than mammals. Little is known 

 about the non-mammalian distribution of this hormone. Fellner 

 (198) claims that it may be detected in the eggs of hens and fish, 

 but Doisy and co-workers (167) were unable to confirm this. 



Occurrence in plants. Various workers have claimed that an 

 oestrous reaction may be produced by the use of extracts of 

 various plants. Thus, Loewe, Lange, and Spohr (418) say that 

 an extract of willow catkins gives a positive reaction, and that 

 as much as 200 mouse units may be obtained from a kilogram of 

 fresh material. The stigmata of willow blooms contain a 

 small amount «I4 m.u. per kg.), while the stalks and flowers of 



