connected with the act of reproduction. He gives, however, only a
conjectural and unsatisfactory explanation of its use. (12. Pallas,
Spicilegia Zoolog. fasc. xiii. 1799, p. 24; Desmoulins, Dict. Class.
d Hist. Nat. tom. iii. p. 586.)
In most cases, when only the male emits a strong odour during the
breeding-season, it probably serves to excite or allure the female. We
must not judge on this head by our own taste, for it is well known that
rats are enticed by certain essential oils, and cats by valerian,
substances far from agreeable to us; and that dogs, though they will
not eat carrion, sniff and roll on it. From the reasons given when
discussing the voice of the stag, we may reject the idea that the odour
serves to bring the females from a distance to the males. Active and
long-continued use cannot here have come into play, as in the case of
the vocal organs. The odour emitted must be of considerable importance
to the male, inasmuch as large and complex glands, furnished with
muscles for everting the sack, and for closing or opening the orifice,
have in some cases been developed. The development of these organs is
intelligible through sexual selection, if the most odoriferous males
are the most successful in winning the females, and in leaving
offspring to inherit their gradually perfected glands and odours.
DEVELOPMENT OF THE HAIR.
We have seen that male quadrupeds often have the hair on their necks
and shoulders much more developed than the females; and many additional
instances could be given. This sometimes serves as a defence to the
male during his battles; but whether the hair in most cases has been
specially developed for this purpose, is very doubtful. We may feel
almost certain that this is not the case, when only a thin and narrow
crest runs along the back; for a crest of this kind would afford
scarcely any protection, and the ridge of the back is not a place
likely to be injured; nevertheless such crests are sometimes confined
to the males, or are much more developed in them than in the females.
Two antelopes, the Tragelaphus scriptus (13. Dr. Gray, Gleanings from
the Menagerie at Knowsley, pl. 28.) (Fig. 70) and Portax picta may be
given as instances. When stags, and the males of the wild goat, are
enraged or terrified, these crests stand erect (14. Judge Caton on the
Wapiti, Transact. Ottawa Acad. Nat. Sciences, 1868, pp. 36, 40;
Blyth, Land and Water, on Capra aegagrus 1867, p. 37.); but it cannot
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