THE SENSES 565 



there are exceptions to this, for horses have been known to eat 

 meat with evident pleasure. The herbivora have a remarkably 

 keen scent ; antelopes and deer have the power of detecting the 

 presence of an enemy a considerable distance away, and it is 

 evident that in most animals the sense of smell plays a more 

 important part in their daily lives than with ourselves. 



The acute sense of smell in the herbivora is a protective 

 mechanism. Their sight, comparatively speaking, is not acute, 

 certainly nothing like so keen as that of the animals by whom 

 they are hunted. Horses are quite conscious of the presence of 

 a lion, and exhibit great alarm and anxiety when one is about. 

 The sense of smell is also popularly believed to afford instruction 

 to animals in distinguishing poisonous from non-poisonous 

 plants, and the organ of Jacobson, which is well developed in 

 the herbivora, was supposed by Cuvier to afford this protection. 

 Smell, however, plays a very unimportant role in this connection. 

 Cattle-poisoning as the result of grazing is common all over the 

 world, and especially in South Africa. Experience is here the 

 best master, and survivors may generally be left on a pasturage 

 known to contain poisonous plants, for they have learnt to avoid 

 them. 



It is through the sense of smell that the male is attracted to 

 the female during the ' cestrous ' season, and not only can the 

 odour of a female in this condition be detected at a considerable 

 distance, but the smell is evidently most persistent. By the 

 sense of smell animals have the power of recognising their own 

 offspring ; a cow which has lost her calf will yield milk for weeks 

 to a ' dummy ' clothed in the skin of the dead calf, and she can 

 recognise the difference between her ' dummy ' and that belong- 

 ing to another cow. If the skin of a young animal, kid, for 

 instance, be dressed with an agent which disguises the body- 

 smell, the mother is unable to recognise her young. The odour 

 of food is readily recognised by the herbivora, though to the 

 human senses all the grains are equally free from any smell 

 but that of the sack which contains them. Without tasting it, 

 a horse will refuse a grain he is not familiar with. It is possible 

 that everything and everybody has a distinctive odour — at least, 

 it would appear to be so from the remarkable manner hounds 

 will follow a scent, or a dog recognise his own master in the dark 

 from amongst a crowd of other persons. In the case of hounds, 

 the amount of odour required to stimulate the olfactory organ 

 must be something too infinitesimal for expression. 



The elevation of the upper lip in the horse is associated with 

 the sense of smell. The stallion, on approaching a mare, ex- 

 hibits this evidence of the pleasurable impression on his olfactory 

 organs, but he does exactly the same after having had a draught 



