854 



SCIENCE. 



[N. S. Vol. XXI. No. 544. 



pigment, and their antenna? are eleven per 

 cent, longer compared with individuals of 

 the same species living outside. 



Guinea-chicken Hyhrids: IMichael F. 



GuYER, University of Cincinnati. 



These hybrids, five in number, were pro- 

 duced by crossing a black Langshang cock 

 with a common guinea hen. AVhen young 

 the hybrids resembled more young guineas, 

 although the shanks were feathered, as were 

 those of the father. Traces of these feath- 

 ers still (nearly three years later) per- 

 sist. The hybrids are much larger than 

 guineas and have louder and even more 

 discordant voices. They are extremely 

 wild. The head shows no trace of either 

 the comb of the chicken or the helmet of 

 the guinea, but is covered with feathers 

 clear to the beak. Neither are wattles 

 nor earlobes present. The beak, in color 

 and shape, resembles more that of the 

 guinea. A trace of the guinea's white face 

 is discernible in the hybrid in the immedi- 

 ate region of the eyes. The neck is very 

 long and snake-like. The feathers are 

 more or less intermediate in structure be- 

 tween those of the parent forms. The 

 tail is erect and never droops like that of 

 the guinea. The large quill feathers of tail 

 and wing not infrequently possess vanes 

 which are black on one side of the raehis 

 and more like the hybrid general plumage 

 on the other. The first one .to three 

 primaries are white in all of the hybrids. 

 Guineas frequently show similar white 

 primaries. The color of the head and neck 

 is mainly black, although in two of the 

 forms, there is a decided sprinkling of 

 white feathers in this region. The general 

 ground color of body, wing and tail plum- 

 age is dark gray in three of the hybrids, 

 but in the remaining two it verges more 

 toward a chestnut color. In all, the feath- 

 ers are crossed by narrow lighter colored 

 V-shaped bars which gives the plumage, on 



the whole, a decidedly barred appearance. 

 The conspicuous white dot of the guinea's 

 plumage seems to be entirely lost. There 

 is, however, a secondary inconspicuous 

 barring in many of the features of the 

 guinea which possibly may be the source 

 of the bars of the hybrid. The forms have 

 not proved fertile and the chief interest 

 in them will center in the chromosomal 

 structures of the germ cells. At present 

 there is no means of telling their sex. 



Notes on Cross-bred Chickens: Michael F. 



GuYER, University of Cincinnati. 



Barred or w'hite Plymouth Rocks and 

 brown Leghorns were used in crossing. 

 There is much question regarding the ex- 

 act ancestry of Plymouth Rocks, but vm- 

 doubtedly the American Dominique and 

 the black Java are the main sources, with 

 probably also a considerable admixture of 

 Brahma blood. The brown Leghorn of to- 

 day appears to be the descendant of an old 

 breed of fowls introduced from Italy in 

 1834. 



The offspring, 400 in number, of brown 

 Leghorn X Plymouth Rock 5 were every 

 one black, except for an occasional feather 

 of reddish hue in some of the cocks. "While 

 in plumage they thus seem to revert to 

 the ancestral black Java, this is not so true 

 of shape and weight, which varies in all 

 degrees between that of the two parent 

 types. The white ear lobes of the Leghorn 

 always persist. Some of the progeny, in- 

 deed, resemble black Minorcas very closely. 

 ]\Iost of them have the dark slate-colored 

 shanks that commonly accompany black 

 fowls, although about 30 per cent, are 

 yellow shanked. The comb is the most 

 variable structure, exhibiting 3 or 4 to 

 7 serrations. Not infrequently double 

 combs (two single ones side by side) ap- 

 pear in the cocks. Various crosses among 

 the members of this generation and between 

 them and the parent stocks were made, but 



