PERCEPTIONS OF ANIMALS. />15 



We see animals providing against the approach of 

 winter, the effects of which they have never expe- 

 rienced, and employing various means of defence 

 against enemies they have never seen. The parent 

 consults the welfare of the offspring she is destined 

 never to behold ; and the young discovers and pur- 

 sues without a guide that species of food which is 

 best adapted to its nature. All these unexplained, 

 and perhaps inexplicable facts, we must content 

 ourselves with classing under the head of instinct ; 

 a name which is, in fact, but the expression of our 

 ignorance of the nature of that agency, of which 

 we cannot but admire the ultimate effects, while we 

 search in vain for the efficient cause. 



In all the inferior orders of the animal creation 

 where instincts are multiplied, while the indications 

 of intellect are feeble, the organ which performs 

 the office of the brain is comparatively small. The 

 sensitive existence of these animals appears to be 

 circumscribed within the perceptions of the mo- 

 ment, and their voluntary actions have reference 

 chiefly to objects which are present to the sense. 

 In proportion as the intellectual faculties of animals 

 are multiplied, and embrace a wider sphere, addi- 

 tional magnitude and complication of structure are 

 given to the nervous substance which is the organ 

 of those faculties. The greater the power of com- 

 bining ideas, and of retaining them in the memory, 

 the greater do we find the developement of the 

 cerebral hemispheres. These parts of the brain 

 are comparatively small, as we have seen, in fishes, 

 reptiles, and the greater number of birds ; but in 

 the mammalia they are expanded in a degree 

 nearly proportional to the extent of memory, saga- 



