The sense which of all others is most deficient in the Cat is that of smell. In this she differs most markedly from the Dog. It is said that a piece of meat may be placed in close proximity to a Cat, but that, if it is kept covered up, she will fail to distinguish it. This want is, however, partly compensated for by an extremely delicate sense of touch, which is possessed, to a remarkable extent, by the whiskers, or vibrissæ, as well as by the general surface of the skin. These bristles, as we have already mentioned in speaking of the Tiger, are possessed to a greater or less extent by all Cats, and are simply greatly developed hairs, having enormously swollen roots, covered with a layer of muscular fibres, with which delicate nerves are connected. By means of these latter, the slightest touch on the extremity of the whiskers is instantly transmitted to the brain. These organs are of the greatest possible value to the Cat in its nocturnal campaigns. When it is deprived of the guidance afforded by light it makes its way by the sense of touch, the fine whiskers touching against every object the Cat passes, and thus acting in precisely the same manner as a blind man’s stick, though with infinitely greater sensibility. Imagine a blind man with not one stick, but a couple of dozen, of exquisite fineness, and these not held in his hand, but embedded in his skin, so that his nerves come into direct contact with them instead of having a layer of skin between, and some notion may be formed of the way in which a Cat uses its whiskers. But the Cat in its night walks has a further advantage over the blind man, namely, that except on the very darkest nights, it is not entirely deprived of the power of sight, for, as we have already mentioned, the pupil is so constructed that in the dark it can be dilated, so as to catch every available ray of light, and, moreover, the _tapetum_, or brilliant lining of the eyeball, reflects and magnifies the straggling beams, and so enables the Cat, if not actually to “see in the dark,” as is sometimes stated, at least to distinguish objects in an amount of light so small as to be inappreciable to our duller vision. As we have already mentioned, the Domestic Cat is less strictly carnivorous than the wild _Felidæ_: still it prefers meat or milk to anything else, and is by no means a miscellaneous feeder, like the Dog. In the matter of diet, Gilbert White remarks[50]--“There is a propensity belonging to common house Cats that is very remarkable. I mean their violent fondness for fish, which appears to be their most favourite food; and yet Nature in this instance seems to have implanted in them an appetite that, unassisted, they know not how to gratify; for, of all quadrupeds, Cats are the least disposed towards water, and will not, when they can avoid it, deign to wet a foot, much less to plunge in that element.” Mr. White does not seem to have known of the habits of the Jaguar.