1900.J SOFT ANATOMY OF THE MUSK-OX. 163 



transverse plicae or valves like those in Ovibos, which may therefore 

 be peculiar to that form. 



. At the ventral angle of the labia pudtndi is the clitoris with 

 a rounded glans. Its visible parts are oviform, 6 mm. long by 

 4 broad. 



The kidneys of Ovibos are bean-shaped, witbout trace of division 

 into lobules. Their dimensions in an old bull are as follows : — 

 length 13 cm., breadth at bilus 6^-7 cm., thickness 4f-5f cm. 

 In a young cow the corresponding dimensions are 11, 6, and 5 cm. 

 When the kidney is cut longitudinally it can be seen that there is 

 only one elongate and ridge like mammilla formed by the more or 

 less complete blending of many cones into one. The cones are, 

 however, at their bases more or less distinct. This character offers 

 a remarkable difference from the corresponding structure in Bos, 

 but agrees with that of the sheep, goats, deer, and other ruminants, 

 even the Cameliclce. It is accordingly a character of importance in 

 distinguishing Bos and Ovibos ; but, on the other hand, it does 

 not prove any closer relationship between Ovibos and Ovis, because 

 Bos is in this respect an aberrant, and Ovibos a normal ruminant. 



Concerning the mammary organs of Ovibos, it is stated by various 

 authors with more or less certainty that the udder is provided with 

 only two teats. This statement is, however, erroneous, as Ovibos, 

 both females and males, normally have four well-developed teats. 

 On the I lth of July, Mr. Arwidson preserved the udder of a young 

 cow shot in Queen Augusta Valley. The udder had four teats, the 

 anterior pair situated 8 cm. apart. The posterior pair measured 

 25 mm. in length, and 4 cm. apart ; the distance between the two 

 pairs being5 cm. On the 26th of August, an old cow, with milk in 

 the udder, was killed at Emperor Franz Joseph Fjord. She had four 

 normal teats and one accessory. The anterior of these measure 

 in the preserved state about 3| cm., and the posterior 4-4| cm. 

 The fifth accessory teat is close to the base of the right anterior 

 one, and is not quite lg cm. long in the preserved state. In a bull 

 -killed in July on Sabine Island, Mr. Arwidson found four teats 

 and a fifth accessory one. " At the base of the scrotum," he 

 writes, " two rudimentary teats were situated 7 cm. apart, 5 cm. 

 in front of these was another pair, and 6 cm. in front of these on 

 the left side still another of small size, but the corresponding one 

 on the right side is missing. The posterior ones are larger, 

 measuring 1-5 cm." The udder of the cow is densely covered with 

 hair, and even the teats, although more sparsely, are beset with 

 hairs of a lighter, nearly white coloration. The aperture in the 

 tip of the teats is large. ' In their shape the teats resemble those 

 of the cow, although smaller and hairy. 



The alleged presence of only two' teats has been regarded as 

 evidence for allying Ovibos with the Ovine Euminants. The opposite 

 view is, perhaps, proved by the existence of four teats. Indeed, 

 the evidence is more than this ; because, if there had only been two, 

 one pair might have been reduced by parallelism, since the presence 

 of two pairs is the primary condition, as may be gathered from 



11* 



