to recognise the corresponding parts on the opposite sides of the body; yet it
is apparently a mere matter of chance whether it be the right or the left side
that undergoes so singular amount of change. One plant is known to me (13/63.
Mormodes ignea: Darwin 'Fertilisation of Orchids' 1862 page 251.) in which the
flower, according as it stands on the one or other side of the spike, is
unequally developed. In all the foregoing cases the two sides are perfectly
symmetrical at an early period of growth. Now, whenever a species is as liable
to be unequally developed on the one as on the other side, we may infer that
the capacity for such development is present, though latent, in the
undeveloped side. And as a reversal of development occasionally occurs in
animals of many kinds, this latent capacity is probably very common.

The best yet simplest cases of characters lying dormant are, perhaps, those
previously given, in which chickens and young pigeons, raised from a cross
between differently coloured birds, are at first of one colour, but in a year
or two acquire feathers of the colour of the other parent; for in this case
the tendency to a change of plumage is clearly latent in the young bird. So it
is with hornless breeds of cattle, some of which acquire small horns as they
grow old. Purely bred black and white bantams, and some other fowls,
occasionally assume, with advancing years, the red feathers of the parent-
species. I will here add a somewhat different case, as it connects in a
striking manner latent characters of two classes. Mr. Hewitt (13/64. 'Journal
of Horticulture' July 1864 page 38. I have had the opportunity of examining
these remarkable feathers through the kindness of Mr. Tegetmeier.) possessed
an excellent Sebright gold-laced bantam hen, which, as she became old, grew
diseased in her ovaria, and assumed male characters. In this breed the males
resemble the females in all respects except in their combs, wattles, spurs,
and instincts; hence it might have been expected that the diseased hen would
have assumed only those masculine characters which are proper to the breed,
but she acquired, in addition, well-arched tail sickle-feathers quite a foot