MAMMARY GLANDS IN UNGULATA. 779 



front of the vulva. The nipples project, one on each side of the 

 mesial line, an inch and a half apart, near the base of the ( pre- 

 putium clitoridis ; ' the lactiferous ducts open, above the base of 

 the nipple, into a large reservoir, which is divided by an internal 

 septum into two chambers, one situated in front, and the other 

 behind; from each chamber a separate duct is derived, which 

 passes along the nipple as far as its extremity, where it termi- 

 nates. The orifices are one behind the other, about a line apart. 

 The rudimental nipples, in the male Equidce, are concealed 

 within the prominent annular preputial fold of integument, and 

 long escaped observation. 1 



The Tapir has two inguinal nipples. The smaller and more 

 prolific Perissodactyle, Hyrax, has four teats, all inguinal in 

 position. 2 



In the Hippopotamus the two teats are inguinal, small, and 

 round in the virgin female. The Peccari has four teats, two 

 ventral, two inguinal. The Wart-hog {Phacocha.rus) has six 

 nipples ; two inguinal, four ventral : the Water-hog (Potamo- 

 chcerus) has eight nipples, and such is sometimes the number in 

 the wild Sow ; but in the domestic breeds the nipples are seldom 

 below ten in number, distributed from the pectoral to the inguinal 

 region. 



All ruminants have the mammary glands compacted into a 

 roundish mass, more or less pendulous when in full function ; 

 divisible into two glands, each remarkable for its large lacteal 

 reservoir, from which the milk is conveyed to either one pair or 

 two pairs of teats ; these, when in use, are so elongated as to 

 have received the special name of ' udders ; ' they are always 

 inguinal in position, are hollow and have a contracted tubular 

 terminal aperture. 



Moschidce, Ovidce, many Antelopes, including the Gazelles, 

 Bubalines, with Bubalus moschatus, have but two teats. An- 

 tilope dama, A. strepsiceros, A. Oreas, and their allies have 

 four teats. All Cervidce, from the great Elk to the little Roe, 

 have four teats ; as have also the Camels, Camelopard, and all 

 Bovines. In some of our domestic cows a supernumerary pair 

 is occasionally developed. Behind each teat, in the Gazelle, 

 there is a pouch of skin, opening forward, about seven lines in 



1 Solidungula mascula mammas non habent. Kai, Synops. method. Anim. quad. &c. 

 p. 64. 



2 Schreber found only this number in Hyrax capensis, as did Ehrenberg in H. 

 Syriacus. Dbsmarest adds a pectoral pair, but this needs confirmation. 



