See Dr. P. Broca's interesting memoir on this subject in Brown-Sequard 'Journ. de. Phys.' volume 2 page 367.), it is possible, though not probable, from the great difficulty in making the first cross, that some of the larger races, which are coloured like the hare, may have been modified by crosses with this animal. Nevertheless, the chief differences in the skeletons of the several domestic breeds cannot, as we shall presently see, have been derived from a cross with the hare.
There are many breeds which transmit their characters more or less truly. Every one has seen the enormous lop-eared rabbits exhibited at our shows; various allied sub-breeds are reared on the Continent, such as the so- called Andalusian, which is said to have a large head with a round forehead, and to attain a greater size than any other kind; another large Paris breed is named the Rouennais, and has a square head; the so-called Patagonian rabbit has remarkably short ears and a large round head. Although I have not seen all these breeds, I feel some doubt about there being any marked difference in the shape of their skulls. (4/8. The skulls of these breeds are briefly described in the 'Journal of Horticulture' May 7, 1861 page 108.) English lop-eared rabbits often weigh 8 pounds or 10 pounds, and one has been exhibited weighing 18 pounds; whereas a full-sized wild rabbit weighs only about 3 1/4 pounds. The head or skull in all the large lop-eared rabbits examined by me is much longer relatively to its breadth than in the wild rabbit. Many of them have loose transverse folds of skin or dewlaps beneath the throat, which can be pulled out so as to reach nearly to the ends of the jaws. Their ears are prodigiously developed, and hang down on each side of their faces. A rabbit was exhibited in 1867 with its two ears, measured from the tip of one to the tip of the other, 22 inches in length, and each ear 5 3/8 inches in breadth. In 1869 one was exhibited with ears, measured in the same manner, 23 1/8 in length and 5 1/2 in breadth; "thus exceeding any rabbit ever exhibited at a prize show." In a common wild rabbit I found that the length of two ears, from tip to tip, was 7 5/8 inches, and the breadth only 1 7/8 inch. The weight of body in the larger rabbits, and the development of their ears, are the qualities which win prizes, and have been carefully selected.
The hare-coloured, or, as it is sometimes called, the Belgian rabbit, differs in nothing except colour from the other large breeds; but Mr. J. Young, of Southampton, a great breeder of this kind, informs me that the females, in all the specimens examined by him, had only six mammae; and this certainly was the case with two females which came into my possession. Mr. B.P. Brent, however, assures me that the number is variable with other domestic rabbits. The common wild rabbit always has ten mammae. The Angora rabbit is remarkable from the length and fineness of its fur, which even on the soles of the feet is of considerable length. This breed is the only one which differs in its mental qualities, for it is said to be much more sociable than other rabbits, and the male shows no wish to destroy its young. (4/9. 'Journal of Horticulture' 1861 page 380.) Two live rabbits were brought to me from Moscow, of about the size of the wild species, but with long soft fur, different from that of the Angora. These Moscow rabbits had pink eyes and were snow-white, excepting the ears, two spots near the nose, the upper and under surface of the tail, and the hinder tarsi, which were blackish-brown. In short, they were coloured nearly like the so-called Himalayan rabbits, presently to be described, and differed from them only in the character of their fur. There are two other breeds which come true to colour, but differ in no other respect, namely silver-greys and chinchillas. Lastly, the Nicard or Dutch rabbit may be mentioned, which varies in colour, and is remarkable from its small size, some specimens weighing only 1 1/4 pounds; rabbits of this breed make excellent nurses for other and more delicate kinds.