CHAPTER XXII. 

 MUSCLES. 



A work of great value to the biologist has been written by one 

 whose work has led him in the widening path of human physiology 

 and its very title is instinct with meaning. The Integrative action 

 of the Nervous System may not aid the systematist or the student 

 of genetics, but for insight into formative powers, where the former 

 can but record facts and find no interpretation, such a work is 

 of supreme importance. When the plant sealed its fate and 

 enclosed itself in a cell-wall and abandoned a life of movement, 

 it was foreordained that its rival would be that cell and its descend- 

 ants which could adopt a free life, and that the future of the world 

 would lie at the proud foot of that conqueror who could command 

 and mobilize the resources of a nervous system. And, as we know, 

 it has fallen to man to receive the rewards of this promise and 

 potency of a higher life. If one seeks to understand the steps by 

 which man has arrived at his primacy it can only be by the highway 

 of nervous progress, however much the tracing of certain connecting 

 or collateral paths may throw light on contributing causes. So 

 that man's place in Nature is nearly synonymous with the structural 

 evolution of his brain, as Huxley has shown in his clear and simple 

 manner. Even if man is to remain still an animal Melchisedec for 

 generations to come, or to put it lower, a foundling, no future 

 discoveries that can be imagined will disprove Huxley's declaration, 

 " Evolution is no longer an hypothesis, but an historical fact." 

 And yet if man has become adapted to his world, and, in it, crowned 

 with glory and honour by the unfolding of some original complexity, 

 or as the result of some fortunate mutations in the distant past, 

 the human brain, with its cranial capacity of nearly three times the 

 number of cubic centimetres to that of the gorilla, has been making 

 false claims to a paramountcy over all factors in the wonderful 

 initiative of fresh capacities and their mobilisation for conquest. 

 Nothing less than such a " claim " was understood by the ancients, 

 and, though metaphysics had to supply the lack of anatomy and 

 physiology, it has always been held that mind was lord of matter, 

 and now scientific research has told us why. But no one, even the 



