MIND AND MEMORY OF BIRDS. 15 



for the influence of the mind upon the body, 

 even in the case of a low animal, is great and 

 manifold. Indeed, I believe that the whole 

 matter of physical modification in animals 

 brought about by the exigencies of change in 

 environment, is referable, in an obscure and 

 indirect way, to that influence. What we 

 attempt to express by the word desire is 

 nothing more than a natural (though it may 

 be a sadly debased) impulse toward another 

 state. In its broadest and freest sense desire 

 is merely the initial effort of a being toward 

 a new experience or a lost estate; in other 

 words, it is the consciousness of a need 

 coupled with an impulse in the direction ob- 

 taining it. The mind-cure fraud is based 

 upon the efficacy of desire. The concentra- 

 tion of the mind upon any particular part of 

 the body certainly affects the part, and the 

 effect may be to produce local disturbance of 

 a peculiar kind, or to destroy a result of local 

 lesion, provided the lesion be not more than 

 a disturbance of nervous equilibrium. From 

 the point of view thus taken one may see 

 one's way clear to an inference as simple as it 

 is strong : evolution is the outcome of natu- 

 ral desire, and natural desire has been gener- 

 ated by a disturbance of natural equilibrium. 

 There is nothing abstruse or occult in this 

 proposition ; it is merely a recognition of the 

 development of ^intelligence and of the con- 

 trolling power of the brain in animals. 



Professor Marsh, in the course of his ad- 

 mirable monograph on the Odontornithes, 

 or ancient toothed birds, suggests that cer- 

 tain wingless species had become so by non- 

 tmer of the organs of flight, Perhaps the 

 limit of this proposition would be found coin- 

 ciding yiiih, that of brain-influence above 



