Page:The Zoologist, 4th series, vol 5 (1901).djvu/353

Rh recognize at once that its thought must take the colour of the sense by which they are chiefly prompted. A Dog, for example, does not recognize 'a family likeness,' but a family smell. In a day of happy wandering down the village street, and through the lanes, it pays no attention to the picturesque. As it lies in front of the fire, reviewing the experiences of the day, it recalls a long succession of suggestive smells. It is the cheek-bristles of the Otter which vibrate with excitement as it remembers the slipperysided Salmon it nearly mistook for an alder-root. The Cat twitches its ears as it dreams of bursting unannounced into a seminary of Mice. If we wish in any degree to realize what our thoughts would be like if we were to exchange our brain for the brain of some other animal, we must ask, first. Which of the five sense organs is the one through which this particular animal chiefly looks out upon the world?" Again:—"We see with the clearness of the lower vertebrates—birds, reptiles, and fishes, in which vision is mono-scopic—although we, in common with Monkeys, and some other of the higher vertebrates, have acquired the power of stereoscopic vision." Jordan and Kellogg, in a recent volume in which the theory of mimicry is treated as an absolute fact, still remark:—"It will be recognized that in the study of how other animals feel and taste and smell and hear and see, we shall have to base all our study on our own experience. We know of hearing and seeing only by what we know of our own hearing and seeing; but by examination of the structure of the hearing and seeing organs of certain other animals, and by observation and experiments, zoologists are convinced that some animals hear sounds that we cannot hear, and some see colours that we cannot see." If we consider the lives of purely nocturnal animals, the fact is impressed on our minds with irresistible force, that the world they see and know must have a totally different aspect to what we realize by the light of day, whilst their living environment is also under different conditions. Except on moonlight nights darkness must reign supreme, whilst a general silence replaces the hum of animal life, and nature ever seems to sleep. Such must be the experi-