206 Evolution and Adaptation 
present in both sexes. In the shrew mice, abdominal scent 
glands are present, but since these mice are rejected by birds 
of prey, their glands probably serve to protect them ; “never- 
theless the glands become enlarged in the males during the 
breeding season.” In many other quadrupeds the scent 
glands are of the same size in both sexes, and their func- 
tion is unknown. 
“In other species the glands are confined to the males, or 
are more developed than in the females; and they almost 
always become more active during the rutting season. At 
this period the glands on the sides of the face of the male 
elephant enlarge, and emit a secretion having a strong musky 
odor. The males, and rarely the females, of many kinds of 
bats have glands and protrudable sacs situated in various 
parts; and it is believed that these are odoriferous. 
“The rank effluvium of the male goat is well known, and 
that of certain male deer is wonderfully strong and persist- 
ent. Besides the general odor, permeating the whole body 
of certain ruminants (for instance, Bos moschatus) in the 
breeding season, many deer, antelopes, sheep, and goats, 
possess odoriferous glands in various situations, more es- 
pecially on their faces. The so-called tear-sacs, or subor- 
bital pits, come under this head. These glands secrete a 
semifluid fetid matter which is sometimes so copious as to 
stain the whole face, as I have myself seen in an antelope. 
They are ‘usually larger in the male than in the female, 
and their development is checked by castration.’ According 
to Desmarest they are altogether absent in the female of 
Antilope subgutturosa. Hence, there can be no doubt that 
they stand in close relation with the reproductive functions. 
They are also sometimes present, and sometimes absent, in 
nearly allied forms. In the adult male musk-deer (Moschus 
moschiferus), a naked space round the tail is bedewed with 
an odoriferous fluid, whilst in the adult female and in the 
male until two years old, this space is covered with hair, and 
