668 Sex in Parabiotic Twins 



7. Sex development in the newt is greatly affected by parabiosis with sala- 

 manders. The detailed analysis leads to the conclusions: 



a. That both sexes of salamanders release corticin as well as medullarin, 

 though in different proportions and 



b. That the growth of ovaries and testes is controlled by gonadal growth 

 substances. 



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15. Witschi, E.: Cold Spring Harbor Sympsa. Quantit. Biol. 10:145, ^9A-- 



\ 



