ANIMAL INSTINCTS, 155 



life ? This, in fact, is the main question embodied in 

 Mr. Darwin's doctrine of the Origin of Species. A 

 negative answer to it can only be reached through 

 the proof that there are classes of instincts which 

 cannot belong to any visible or conceivable bodily 

 organisation. 



I have already spoken on this point, expressing my 

 belief that there are instincts thus characterised, and 

 not otherwise to be interpreted to our conceptions than 

 as original in the species or genus to which the animal 

 belongs. The lower organisms are those in which the 

 instincts of life are simplest and most absolute. As we 

 rise upwards the more complex structure gives greater 

 liability to disturbance from outward causes, and in 

 the higher animals we find the influence of intelligence 

 and feeling and the habits generated thereby. But in 

 all these grades of being phenomena come before us 

 which no organisation, though deciphered by the 

 subtlest anatomy or physiology of the vital functions, 

 can explain. In numerous cases, indeed, specialties of 

 structure are seen, necessary to the special instincts to 

 which they subserve. But this falls far short of proof 

 that structure alone has generated the instinct. The 

 powerful muscles and other structural peculiarities of 

 certain birds and fishes are necessary to their periodical 

 migrations by land and sea. But the act of migration 

 itself is the marvel determinate as to place, time, and 

 method guided by no sense or reason we can define 

 or conceive, yet fulfilling its purposes with a certi- 

 tude no reason could attain. Numerous animals have 

 special apparatus adapted to objects wholly prospective, 



