ANIMAL SENSE PERCEPTIONS. 325 



recognize at once that its thought must take the colour of the 

 sense by which they are chielly 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 slippery- 

 sided 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. "t Jordan and Kel- 

 logg, 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- 



-■■ ' Introduction to Science' (Temple Encyelop. Primers), p. 32. 



f Ibid. p. 38. 



J ' Animal Life,' pp. 224-5, 



