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 liatched from the fiftli, 

 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 eggs. I can only account for tlie 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 j)arents and of the ripeness of the germ-cells. 



Similar results having been obtained with other pigeons, I next turned my 

 attention to rabbits, j^artly because the}'' 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. Fui'ther, in 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 

 gradually 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 GaUoway buU is mated with long-homed, long-haii-ed, yeUow 

 or red Highland heifers — cattle undoubtedly of an older type than the Galloways. The oifspring 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 

 GaUoway bull, the calves, it is said, may be either yellow, red, or black, and sometimes they are provided 

 with distinct vestiges of horns. 



TRANS. EOY. DTTB. SOC., N.S. VOL. VII., PART. XIU. 3 E 



