454 THE ZOOLOGIST. 



held, but one might ask in what way are these members of the 

 TJr sides and Bovides, above mentioned, " more different " re- 

 spectively from each other than the Horse and the Ass ? The 

 only reply that I should expect to this question would be that 

 they are considered by some authorities to be structurally so, 

 and that by some naturalists they have even been placed in 

 different genera. We have thus, on the one hand, this some- 

 what dogmatic assertion : first, that the difference between two 

 carnivores of similar gait, fish-eating and climbing propensities, 

 and both omnivorous ; and, secondly, that the difference between 

 two plain-haunting, grass-eating members of the family Bovides 

 (Bison and Cattle) is greater than that between the plain- 

 haunting, broad-hoofed Horse (a blundering galloper through 

 shallow pools, with an eleven months' gestation) and the desert 

 and mountain-loving, small-hoofed, dust-rolling, thick-skinned 

 Ass, whom one can hardly force across the shallowest streams, 

 and whose gestation extends to thirteen months. Well, it may 

 be so ! 



Besides all the above points, however, there appears to me a 

 certain possession of habits and individuality which the Bison 

 and Cow possess in common, and which the two Bears likewise 

 possess, and which seems to be quite wanting in the two above- 

 mentioned members of the Equities. There is also in the latter 

 a difference that can be observed in the actions attendant upon 

 copulation. Further, there is also this difference between the 

 latter, which I do not think exists in the two former groups 

 (I certainly cannot detect it). If will not be found mentioned in 

 popular writings or in the text-books, but it may be one of some 

 importance for all that. It is a difference one can detect without 

 any post-mortem examinations of the animals, without touching 

 them, without looking at them, without even going near them. 



If the reader will go into any stable where Donkeys are kept, 

 and into one where Horses are kept, he will immediately perceive 

 this difference, for he will smell it. Our human sense of smell 

 is a very poor one, and we therefore seem to neglect this mode 

 of classification, which is perhaps the only one animals know of, 

 and which it is possible is better than all ours put together. 

 We can certainly detect the difference between a he-Goat and 

 she-Goat a furlong away if we are to leeward, and the difference 



