298 Referate. 
spezifische chemische Substanzen (z. B. die Hormonentheorie Cunninghams) 
gebildet werden, welche unter Vermittlung des Blutes gleichzeitig adäquate 
Veränderungen am Körper und im Keimplasma hervorbringen. 
Kammerer, Wien. 
Guyer, M.F. Atavism in Guinea-chieken hybrids. Jour. Exper. Zool. 7 1909, 
pp- 723—745. Pl. I—IV. 
This paper has to do with a description of five adult hybrids said to 
have resulted from the crossing of a Black Langshan 3 (Gallus domesticus) 
with a domestic Guinea-hen 2 (Numida meleagris). This crossing was not 
made experimentally by the author, but instead the hybrids came into his 
possession only when nearly three years old. No information is given 
regarding the circumstances of the mating, nor is any evidence, other than 
that arising from examination of the birds themselves, presented to show 
that these hybrids really originated in the manner stated. This is a 
regrettable omission. All of the hybrids are males, but curiously enough 
none bear spurs. In regard to weight and size they “approximate more 
closely to the male parent”. “In general configuration of the body they 
are about intermediate between the chicken and the guinea. The plumage 
and ornamentation of the hybrids, however, is more generalized than that 
of either parent.” As young chicks the hybrids are said to have resembled 
young guineas, but with advancing age they took on more and more fowl 
characteristics. At five years of age the two birds then surviving each 
developed a pair of sickle feathers in the tail like those characteristic of 
the domestic cock. Such feathers are not found in the 3 guinea. The 
hybrids were throughout life extremely wild, though frequently handled. 
“The striking feature in the plumage of all these hybrids is that most of 
the feathers exhibit a pronounced vermiculation of successive, narrow, 
whitish, U-shaped bands which gives the plumage as a whole the appearance 
of being barred.... In three of the fowls the general ground color is 
blackish and the vermiculations white, in the other two there is much of 
a reddish brown or chestnut tinge to many of the feathers, involving also 
to some extent the whitish bands so that there is less contrast in the 
color markings.” 
The bulk of the paper is devoted to an attempt to “explain” this 
“vermiculation” pattern of the plumage of the hybrids as a reversion to 
remote ancestors of the parent forms. Following a rather extensive dis- 
cussion of the types of color pattern seen in different members of the sub- 
families Phasianinae and Numidinae the following conclusions are reached: 
‘The charakteristic color pattern of white U-shaped vermiculations on a 
dark background is a return to a generalized type of color marking that 
is more or less recognizable in various groups of the sub-families Phaszaninae 
and Nwmidinae. The immediate pattern as seen in these hybrids is seemingly 
a composite of primitive loop-like bands as exemplified in Zolyplectron 
chalcurus together with the prevalent stripe of the more specialized phea- 
sants, on the one hand, and, on the other, of the numerous transverse 
vermiculations of an ancestral color pattern approximating that of Agelastes 
meleagrides. The short black feathers of the neck found in all of these 
pronounced hybrids seem, as already indicated, to approach more nearly 
the condition of the feathers found on the neck of Gallus ferrugineus during 
the summer months. The even feathering of the head and loss of orna- 
mentation appears, however, to be yet more primitive, approaching the 
simpler types of Polyplectron. The total lack of spurs in the genus Vwmida 
