1910.] CUTANEOUS SCE.Vr-GLAXDS OF RUMIXAXTS'. 973 



the heel are continued farther backwards. In other words, it is 

 only a diflerence in the degree of development of the parts 

 composing the distal portion of tlie foot. 



As is well known, the plantar area of the hoof in late foetal 

 and many, perhaps all, newly born Oervidas and Bovidte is quite 

 soft right up to and in some cases beyond the apex of the nail. 

 This terminal portion soon shrivels and hardens, and liecomes, in 

 most cases at all events, indistinguishable from the inferior 

 portions of the nail, especially externally ; but usually the line of 

 demarcation between the nail and the sole can be quite easily 

 detected, especially on the inner aspect of the hoof, showing that 

 the sole, although hard and horny, still persists and foi'ms with 

 the heels the main area of suppoi't during progi-ession. The one 

 exception to this rule known to me is the Klipspi-iuger, which 

 appears to support itself entirely upon the ti'uncated apex of the 

 nail of the hoof, with possibly a small piece of the hardened sole 

 wedged in the angle formed by the two sides of the nail. 



The males both of Camelus dromedarius and of C. hactrianus 

 have a pair of well-developed glands on the summit of the neck 

 just behind the occiput. In the living animal these may be easily 

 felt as a pair of oval or roundish lumps lying close together. The 

 hair overlying them has no underwool. In a male of C. drome- 

 darius I have seen black watery secretion running from these 

 glands and dropping ofi" the hairs like sweat. This was in the 

 month of June, when the glands of a male C. bactrianus were 

 quite inactive. In the latter animal the glands were active and 

 giving oft" a powerful repulsive odour much earlier in the year — 

 that is to say, in March. The smell of the secretion from the 

 glands in the Dromedary was equally repulsive, but reminded me 

 of no substance in particular. It stains the skin of the fingers in 

 much the same way as walnut-juice does. The position of the 

 glands in the Dromedary is easily seen by the post- occipital patch 

 of black hair. I have had no opportunity of observing the gland 

 in the female Dromedaiy ; but in the female Bactrian Camel it is 

 much smaller than in the male, and never apparently noticeably 

 active as it is in the latter when ruttinof. 



Function of the Glands, 



I do not know who first ))ropounded the theoiy that the use 

 of the cutaneous scent-glands in Ruminants is to keep the indi- 

 viduals of a species together. As early as 1836 Owen discussed 

 this view ; but, finding that the glands were present in some 

 species of Antelopes of solitary habits and absent in some gre- 

 garious forms, he dropped this hj'pothesis as untenable. He does 

 not appear, however, to have attached sufficient importance to 

 the mutual need of discovering each other on the part of the 

 sexes of solitary species at the breeding-season, nor to the 

 necessity of the mother and young being together, at all events 



