196 MICHAEL F. GUYER. 



first place it is known that sterile females sometimes, although 

 rarely, take on the male plumage, and it may be urged that there 

 is no means of knowing certainly that the sex was determined 

 beyond all doubt by opening the abdominal cavity and finding the 

 testes. However, since the specimens had to be partially dis- 

 sected before the skins could be mounted, it is reasonable to sup- 

 pose that in the vast majority of cases the sex was thus accurately 

 determined. The five guinea-chicken hybrids as well as the six 

 dove and pigeon hybrids mentioned in my former paper were all 

 dissected by me personally and consequently I am sure of their 

 sex. 



In the second place the objection may be raised that possibly 

 the museums have preserved only the males, inasmuch as they 

 make handsomer specimens and are not as similar in appearance 

 as female pheasants. There is, of course, a possibility of this, 

 especially in the case of hybrid pheasants from closely related 

 species. Hybrids from widely different parents are so rare, how- 

 ever, that there is every probability that if there had been females 

 they as well as the males would have been preserved. As a 

 matter of fact, the few female pheasant hybrids that I have been 

 able to find in museums are not similar in appearance nor do they 

 resemble the males. As hybrids they are as interesting in every 

 way as the. males and it seems probable, therefore, that had there 

 been more of them they would have been preserved. When due 

 allowance is made for all errors the facts still indicate that there 

 is a marked tendency for hybrids, especially those from widely 

 separated parents, to be male. 



Lastly, there is the remote possibility that there has been 

 a greater mortality among the females in early life. In the few 

 cases (guinea-chicken hybrids and various pigeon hybrids) of 

 which I have data regarding the number of eggs laid and the 

 history of the young, there is no evidence of such mortality. 



It may be noted in passing that in the collections of the British 

 Museum there is to be seen a hybrid between individuals of two 

 different families, namely, a penelope (Family Cracidae) and the 

 common fowl (Family P hasianidse). This hybrid resembles 

 more the fowl than the penelope. Unfortunately the sex is not 

 recorded. 



