CLIMBING ORGANS 



vation will doubtless settle the point. It has been 

 suggested that they are of the nature of " climbing 

 irons," and aid the lemur in barking up a tree ; but 

 with an excellent and delicately fashioned hand such 

 adjuncts appear to be unnecessary. Besides, why 

 should the structure be different in the two sexes, if it 

 be of this or an analogous direct use. More probably 

 it is one of those mysterious marks of sex which often 

 have no ascertained uses, such as the moustaches of the 

 male man and the different colours of the plumage in 

 many birds. 



THE UNGULATA, OR HOOFED MAMMALS 



Horns and hoofs are the distinguishing feature of this 

 large order of mammals ; they are, furthermore, 

 graminivorous, or, at least, vegetarian in habit, and, 

 as a rule, walk upon the tips of the toes. But an inspec- 

 tion of the various Ungulates contained in the menagerie 

 in London will show that some of these characters do 

 not absolutely define every member of the order. The 

 Hyrax, for example, walks firmly upon the sole of its 

 foot, and has no horns. The elephant has no horns. 

 These two animals are, in fact, representatives of 

 Ungulates of a more primitive structure than the rest. 

 The very earliest known members of the order, now 

 extinct, had not acquired the more typical ungulate 

 characteristics of their descendants of to-day. In many 

 respects they showed symptoms of fading into other 

 orders of mammals, particularly the Creodonta, the 

 ancestors of the Carnivora of the present day. It 

 remains, however, the fact that, though some Ungulates 

 have not got horns, the existence of horns is absolutely 

 confined to this order. In zoological classification even 

 the veriest beginner soon learns that Nature draws no 

 hard and fast lines, and that when an attempt to make 



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