HYBRIDIZATION EXPERIMENTS. 25 
No. 3.—Hypbrid Cock and Hybrid Hen. 
This experiment was the crux of the whole problem before the 
experimenters. It was the experiment Mr. Mitford tried and failed 
to produce chicks. It was the experiment that led Darwin to 
conclude that the hybrids of Gallus Stanleyii were sterile. If the 
experimenters could only breed from this mating, the whole question 
would be settled at once and for ever, and the little Ceylon jungle 
fowl would have the honour of being acknowledged a parent stock. 
The result so far has been a complete failure to produce chickens ! 
Some three or four hybrid cocks have been mated up in various 
runs with some four or five hybrid hens. Thus Mr. Mitford’s one 
experiment has been’ multiplied four-fold. Each hen has 
laid several clutches of eggs, but so far no single chick has been 
produced. The eggs have been incubated by the hybrids them- 
selves and also under other hens ; but no chicks. The large majority 
of the eggs have been infertile ; only in one or two instances have 
two or three of the eggs been addled, which points to the egg having 
been fertilized. 
In some of these experimental runs the cock has been seen to 
tread the hens, and yet the eggs were infertile. In the Queensdown 
run the hybrid cock has never been seen to tread a hybrid hen ; 
it is not surprising therefore that all the eggs laid by the hybrids 
were infertile ; it would have been the same with eggs of any other 
neglected hen. 
Some have suggested that since all the hybrids were produced 
by one pair of parents, and are therefore brothers and _ sisters, 
perhaps they may not be able to interbreed. But this would 
hardly be a serious objection to, or sufficient excuse for, infertility. 
An interesting point worth recording about breeding from a 
hybrid cock is this. When a hybrid cock has the choice of mating 
up with either of the four following hens: (1) Domestic ; (2) (4 J + 3 
D) ; (3) hybrid ; (4) jungle ; he would take up with them in the order 
named. He would never look at any of the other three if he had 
a domestic hen to attend. The domestic hen is relatively a little 
wanton, so gentle, tame, and amenable! If she be removed from 
the run the cock will then mate up with the next most domestic of 
the hens, 7.e., No. (2) (1 J + 2D). She is not so wild and will 
stand better than the remaining two. A hybrid cock has not yet 
been tried with only hybrid and jungle hens, but if he were and he 
did mate up, it would certainly be with the moré domestic of the 
two, 2.e., the hybrid. The jungle hen is far too wild and timid in 
captivity and frightened even of a cock bird. Hence the difficulty 
of breeding from them with the domestic cock ; they are friendly 
E 10(2)06 
