rally of a nearly black colour, but soon become grey, and get
whiter and whiter as they grow older. Hence the usual rule is that
Himalayans are born white and afterwards become in certain parts of their
bodies dark-coloured; whilst {110} silver-greys are born black and
afterwards become sprinkled with white. Exceptions, however, and of a
directly opposite nature, occasionally occur in both cases. For young
silver-greys are sometimes born in warrens, as I hear from Mr. W. Birch, of
a cream-colour, but these young animals ultimately become black, The
Himalayans, on the other hand, sometimes produce, as is stated by an
experienced amateur,[264] a single black young one in a litter; but such,
before two months elapse, become perfectly white.

To sum up the whole curious case: wild silver-greys may be considered as
black rabbits which become grey at an early period of life. When they are
crossed with common rabbits, the offspring are said not to have blended
colours, but to take after either parent; and in this respect they resemble
black and albino varieties of most quadrupeds, which often transmit their
colours in this same manner. When they are crossed with chinchillas, that
is, with a paler sub-variety, the young are at first pure albinoes, but
soon become dark-coloured in certain parts of their bodies, and are then
called Himalayans. The young Himalayans, however, are sometimes at first
either pale grey or completely black, in either case changing after a time
to white. In a future chapter I shall advance a large body of facts showing
that, when two varieties are crossed both of which differ in colour from
their parent-stock, there is a strong tendency in the young to revert to
the aboriginal colour; and what is very remarkable, this reversion
occasionally supervenes, not before birth, but during the growth of the
animal. Hence, if it could be shown that silver-greys and chinchillas were
the offspring of a cross between a black and albino variety with the
colours intimately blended--a supposition in itself not improbable, and
supported by the circumstance of silver-greys in warrens sometimes
producing creamy-white young, which ultimately become black--then all the
above-given paradoxical facts on the changes of colour in silver-greys and
in their descendants the Himalayans would come under the law of reversion,
supervening at different periods of growth and in different degrees, either
to the original black or to the orig