1878.] The Senses of the Lower Animals. 297 
Terai, of the Gold-coast, or of the Tierras Calientes smells 
to us exactly like pure, ordinary, wholesome air. On the 
other hand, a wholesome and even delicious fruit, like the 
durrian, may have a most disgustingly repulsive odour. 
Nor can we by this sense discover what track a missing 
friend has taken, or pursue the footsteps of an enemy. In 
the lower Mammalia this is almost reversed. Concerning 
the delicacy of scent in dogs many interesting faCts have 
been brought forward, and not a little “ tall talk ” has been 
perpetrated. But their scent differs from our own not 
merely in its power of detecting odours which escape us 
altogether ; they are evidently gratified by the smell of 
carrion, of ordure, of animal excretions and secretions, 
which to us are utterly offensive. But if the scent of dogs 
has attracted more prominent attention from the circum- 
stance that it is at the disposal of man in hunting, that of 
other Mammalia is little, if at all, inferior. Animals of the 
weasel tribe pursue their prey by scent, and even hunt in 
packs. Swine can follow their companions by the same 
clue, and, as it is well known, have been trained to discover 
truffles under ground. Elephants, deer, bears, and in faCt 
many other wild animals, can only be approached with 
safety from the lee-side, as they otherwise soon become 
aware that an enemy is at hand. Rats have a delicate 
scent, and in setting traps or poison for them it is necessary 
to avoid touching the bait with the hand ; otherwise their 
suspicions are at once aroused. Almost all animals seem 
to know — at least as far as the productions of their own 
locality are concerned — by the odour whether any substance 
is suitable for food, and this faCt has accordingly been 
enlarged upon as a marvellous case of “ instinCt.” Very 
many species are also decidedly attracted by odours which 
have no connection with their food, and which are to them, 
therefore, a mere luxury. The fondness for valerian, 
lemon-thyme, chamomile, lavender, and many plants rich 
in essential oils, is common to the whole feline family. On 
the other hand, they have their dislikes. We have often 
observed the domestic cat smell at a fig-tree, and turn away 
with the air of a disgusted connoisseur. Carbolic acid and 
the coal-tar products generally seem to be an abomination 
to everything that comes under the head of “ vermin. 5 ’ Oil 
of rhodium, on the contrary, has a wonderful fascination for 
rats and mice, and is said to be a prominent ingredient in 
the mixture which enables the modern housebreaker to lull 
even the most vigilant watch-dog into a temporary negleCt 
of duty. 
