TESTS FOR REFRACTORINESS 757 



indirect evidence that light-induced release of gonadotropins from 

 the pituitary was not materially blocked by a refractory condition. 



SUMMARY 



When groups of bobwhite quail hens of different ages and breed- 

 ing histories were given the same interrupted dark period treatment, 

 positive ovarian and oviduct responses, regardless of the length of 

 the postlaying rest, showed that such rest is not required before 

 another period of production can be induced. The accumulated evi- 

 dence is strong that postlaying bobwhite hens are not refractory in the 

 usual sense as applied to passerine birds. 



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