TESTS FOR REFRACTORINESS 753 



the testicular cycle (Burger, 1949; Marshall, 1951). Wolfson (1952) 

 studied the refractory period in female juncos, but the existence of 

 refractoriness in female Galhformes remained uninvestigated. The 

 only source of information may be analogies from domesticated 

 species, but there is always the hazard of reasoning from domesticated 

 to wild species. An interesting clue is found in a minor experiment 

 with bobwhites in which three hens and one cock were under con- 

 tinuous light for more than a year. Fertile eggs were laid by all hens 

 for 223 days and by one hen for 344 days (Baldini et ai, 1954). 

 This evidence, admittedly from small numbers, is not in agreement 

 with one of the aspects of the refractory period as defined for pas- 

 serines, namely, that in quail the breeding condition was maintained 

 indefinitely by light treatment. It appeared that quail likewise may 

 not conform to the other aspect of the refractory condition. If quail 

 hens gave a positive response to light stimulation, applied at different 

 intervals after a period of natural reproduction, the case for no 

 refractoriness in quail hens would be strengthened. Experiments were 

 undertaken to investigate this question. 



MATERIALS AND METHODS 



Six groups of female bobwhites differing in respect to breeding 

 condition were compared following similar light treatments. The 

 physical facilities were similar to those detailed for earlier experiments 

 (Kirkpatrick, 1955). Each group was exposed 42 or 43 days to an 

 intensity of 30 to 35 ft-c on a 24-hr cycle divided as follows: 9 hr 

 of light, 7 hr of darkness, 1 hr of light, 7 hr of darkness. The birds 

 were held two or three to a cage with individuals from groups A, B, 

 and C (Table I) mixed in each cage to insure the same average 

 environmental conditions for those groups. At the end of the exposure 

 periods the birds were sacrificed and the excised organ weights deter- 

 mined to the nearest milligram. The values shown in Table I are 

 averages for the individual ratios comprising each group. 



The groups for comparison were selected especially for their 

 differences in breeding history. All birds in the A groups were of the 

 same age. Groups Al and A2 had experienced a season of normal 

 reproduction in outdoor cages. Groups A3 and A4 had been pre- 



