278 Secondary Sexual Characters in Pheasants 



the leg colour, the Fj, F^, and F^ female offspring are hybrids notwith- 

 standing the three doses of Silver $ to one of Swinhoe </ . 



The birds dealt with in this experiment were obtained by the series 

 of crosses shown in the preceding pedigree of mating. 



We will consider the characters of the birds produced by these 

 matings under two headings, dealing first with time of maturity, 

 plumage and leg colour; secondly with the moulting habits and 

 pattern transference. 



1. Time of Maturity, Plumage and Leg Colour. 



From 1906 to 1909 it is recorded that the two parent species in 

 this cross-breeding experiment were, both male and female, immature 

 at ten months old, and did not breed, but the hybrids F^ " BA " and 

 F2 " BBA " matured in the first year and bred when mated at ten 

 months old. There was an increase in size accompanied by premature 

 sexual development, but not by secondary sexual development. In the 

 second year as in the parent species the adult plumage was assumed. 



In 1910, at ten months old, F^ "BBBA" J $ were penned separately 

 fi-om Fs " BBBA " </ </ ^^^ they laid no eggs ; but in my pheasant 

 experiments, extending over seven years, frequent instances have been 

 recorded of hens not laying when penned apart from cocks in the mating 

 season, therefore this was not absolute proof of immaturity. 



The records of 1911 remark that F^ " BA " 1907 birds mated inter se 

 were laying well, and raising healthy offspring, and that F^ " BBBA " 

 1909 birds mated inter se were very fertile, hatching 13 birds out of 

 14 eggs, 12 of which were reared; it is noted that these F^ "BBBA " 

 inter se as chicks were strong, healthy, and displayed great courage. 



In 1912, during the mating season, the F^ " BBBA " inter se ^ ^ 

 were separated from the F^ ''BBBA" inter se ^ (} under the same 

 conditions as F^ in 1910, i.e. kept in adjacent pens with a wire netting 

 to keep them apart, and though these unmated % % laid no eggs, being 

 possibly immature at ten months, yet four of the % % attacked and 

 beat the fifth % so that it had to be removed, which, occurring during 

 the mating season, must be attributed to rivalry. 



When selecting from the 5 F^ ''BBA " ^/'c/ in 1909 a male parent 

 to cross with a Silver $ , the most mixed looking hybrid was chosen, 

 which in the following summer assumed like the brothers the Silver 



^ By the term "hybrid" is meant the blending of characters derived from the two 

 original parents, due to the simultaneous presence of factors derived from each parent and 

 patently exhibited in the offspring. 



