Ewart— Variation: Germinal and Environmental. 361 
the first, notwithstanding the fact that the surroundings have been as nearly as 
possible the same since the parents were first mated—the food, temperature, light, 
&c., having been practically constant. No birds were hatched from the fifth, 
sixth, and seventh nests, and before the eight pair of eggs were laid the hen bird 
was out of condition. Perhaps for this reason the single bird obtained from the 
eighth nest more closely resembled the turbit than those hatched from the first 
pair of egos. I can only account for the marked contrast between the first and the 
subsequent young by saying, that as the female parent increased in age and vigour 
her germ-cells increased in prepotency.* 
(4). The influence of age of the parents and of the ripeness of the germ-cells. 
Similar results having been obtained with other pigeons, I next turned my 
attention to rabbits, partly because they offered better facilities than pigeons for 
further experiments, and partly because I was anxious, if possible, to discover 
what has always struck me as a very remarkable phenomenon 
why the members 
of a given family, brood, or litter sometimes so decidedly differ from each 
other. 
Finding wild rabbits excessively timid, and, except in rare cases, all but 
untamable, I decided to use half-wild specimens. Having made sure that a 
number of tame white does bred pure, I set them free in an old sand-pit, and ere 
long had a large number of half-wild young at my disposal. I also succeeded in 
breeding half-wild specimens, by mating wild does with a large white Angora. 
All the half-wild rabbits bred were in every respect extremely like pure wild 
rabbits both in form and colour. The half-breeds by the Angora not only resembled 
the common wild form in colour, but also in being excessively timid and quick 
in their movements. Further, m their attitudes, they resembled wild rabbits, 
more especially in keeping the ears, as is the custom of wild rabbits when 
crouching, pressed firmly over the shoulders. Some of the half-breeds were of a 
light-grey colour to start with, but as they grew older the wild colour was 
eradually assumed, the characteristic dark hairs of the ears and tail being always 
present. 
* Some of the results obtained by breeders also support the view that the age is influential in determining 
the character of the offspring. For some reason or other Galloway cattle are extremely prepotent. This 
prepotency is strikingly illustrated when a Galloway bull is mated with long-horned, long-haired, yellow 
or red Highland heifers—cattle undoubtedly of an older type than the Galloways. The offspring of these 
unions are sometimes so like the black hornless parent that experts are unable to say which members of a 
herd are crosses, which pure Galloways. When, however, old Highland cows are crossed with a young 
Galloway bull, the calves, it is said, may be either yellow, red, or black, and sometimes they are provided 
with distinct vestiges of horns. 
TRANS. ROY. DUB. SOC., N.S. VOL. VII., PART. XIII. 3 E 
