abnormal development in them. In the reindeer, on the other hand, the
female is provided with horns; so that in this species, the horns
ought, according to our rule, to appear early in life, long before the
two sexes are mature and have come to differ much in constitution. In
all the other species the horns ought to appear later in life, which
would lead to their development in that sex alone, in which they first
appeared in the progenitor of the whole Family. Now in seven species,
belonging to distinct sections of the family and inhabiting different
regions, in which the stags alone bear horns, I find that the horns
first appear at periods, varying from nine months after birth in the
roebuck, to ten, twelve or even more months in the stags of the six
other and larger species. (39. I am much obliged to Mr. Cupples for
having made enquiries for me in regard to the Roebuck and Red Deer of
Scotland from Mr. Robertson, the experienced head-forester to the
Marquis of Breadalbane. In regard to Fallow-deer, I have to thank Mr.
Eyton and others for information. For the Cervus alces of N. America,
see Land and Water, 1868, pp. 221 and 254; and for the C. Virginianus
and strongyloceros of the same continent, see J.D. Caton, in Ottawa
Acad. of Nat. Sc. 1868, p. 13. For Cervus Eldi of Pegu, see Lieut.
Beaven, Proccedings of the Zoological Society, 1867, p. 762.) But
with the reindeer the case is widely different; for, as I hear from
Prof. Nilsson, who kindly made special enquiries for me in Lapland, the
horns appear in the young animals within four or five weeks after
birth, and at the same time in both sexes. So that here we have a
structure, developed at a most unusually early age in one species of
the family, and likewise common to both sexes in this one species
alone.
In several kinds of antelopes, only the males are provided with horns,
whilst in the greater number both sexes bear horns. With respect to the
period of development, Mr. Blyth informs me that there was at one time
in the Zoological Gardens a young koodoo (Ant. strepsiceros), of which
the males alone are horned, and also the young of a closely-allied
species, the eland (Ant. oreas), in which both sexes are horned. Now it
is in strict conformity with our rule, that in the young male koodoo,
although ten months old, the horns were remarkably small, considering
the size ultimately attained by them; whilst in the young male eland,
although only three months old, the horns were already very much larger
than in the koodoo. It is also a noticeable fact that in the
prong-horned antelope (40. Antilocapra Americana. I have to thank Dr.
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