DARWINISM AND EVOLUTION. 33 



INSTINCTS. 



"VTow, a creature possessing this somewhat improved vision will, 

 -*-* by a partial obscuration of light, have its muscles brought 

 into a state of partial tension — a state fitting them either for the 

 seizure of a small animal, should the partial obscuration be caused 

 . by the pending collision of one ; or for sudden retreat into a 

 shell, should the obscuration be increased by the near approach 

 of a larger animal. 



So, from the simple advance just indicated there arises a 

 somewhat greater speciality and complexity in the inner relations 

 answering to outer relations ; and we see how one of the simpler 

 instincts will, under the requisite conditions, be established by 

 accumulated experiences. 



First we got reflex action, and now we have instinct. 



" Instincts are as important as corporeal structures to the 

 " welfare of each species. With a changing environment, slight 

 " modifications of instinct would become profitable to a species ; 

 " and when instincts do vary, ever so little, then natural selection 

 " can preserve and continually accumulate variations of instinct to 

 "any extent that is profitable." 



MIND AND REASON. 



TTery low in the scale of animal life, the possession of some 

 » general intelligence, that is, of reason, becomes manifest. 

 " Even the headless oyster," says Darwin, " seems to profit by 

 " experience ; " and this is the test of rational as distinguished 

 from instinctive action. 



There are, then, three steps in the evolution of mind. First, 

 the origin of reflex actions ; second, the development of instinctive 

 actions; and last, the attainment of reason. The most complicated 



