The Sense of Smell. 113 
some odours. Dogs do not seem in any instance to take 
pleasure in scents which, like valerian, attract cats. I have 
presented a great number of different flowers, all more or 
less pleasing to us, to the noses of dogs, but never could 
detect any sign of pleasure or aversion in their behaviour. 
Neither have they ever rolled on them when laid on the 
floor, which is the canine mode of expressing delight in carrion. 
Has, then, the odour of the rose, violet, heliotrope, or lavender 
no effect at all on a dog’s sense of smell, or does it merely 
give him no pleasure? He evinces no repugnance to worm- 
wood, aniseed, and some other scents objectionable to us, 
but always turns from essential oils and perfumes, though 
they may be derived from vegetable substances which do 
not affect him when not combined with spirit. It is pro- 
bably, then, the pungency of the alcoholic vehicle that 
repels him. Vegetable odours per se must either be inappre- 
ciable to him or unattractive; all mineral oils are repugnant. 
The animal world is unquestionably the field for the exer- 
cise of his sense of smell, and here its power of discrimi- 
nation is no less remarkable than its acuteness. I have no 
personal experience of the effects of any other scent-pro- 
ducing animals on the dog than the skunk, the mephitic 
odour of which is no doubt as intolerable to us ag to him. 
Few dogs will kill a skunk after once experiencing a shower 
of that noisome secretion, but those that allow their momentary 
pugnacity to overcome their recollection of the infliction are 
a curse to their owners and everyone they approach. 
In view of the indifference or dislike exhibited by the 
dog to odours pleasing to us, his habit of rolling himself in 
carrion of every kind is not easily accounted for. All 
putrescent animal matters appear to have this fascination for 
him, from a dead dog, or cat, or bird, to a frog or a snail. 
Once only have I noticed the indulgence of the habit in the 
case of a vegetable substance. Mr. Hugh Dalziel, however, 
tells me that rolling in decaying cabbage, etc. is by no 
means an uncommon practice. In one of the dense Austra- 
I 
