10 THE DESCENT OF MAN. [Part I. 



quired whether man, like so many other animals, has given 

 rise to varieties and sub-races, differing hut slightly from 

 each other, or to races differing so much that they must be 

 classed as doubtful species ? How are such races distrib- 

 uted over the world ; and how, when crossed, do they react 

 on each other, both in the first and succeeding genera- 

 tions ? And so with many other points. 



The inquirer would next come to the important point, 

 whether man tends to increase at so rapid a rate, as to 

 lead to occasional severe struggles for existence, and con- 

 sequently to beneficial variations, whether in body or 

 mind, being preserved, and injurious ones eliminated. Do 

 the races or species of men, whichever term may be ap- 

 plied, encroach on and replace each other, so that some 

 finally become extinct ? We shall see that all these ques- 

 tions, as indeed is obvious in respect to most of them, 

 must be answered in the affirmative, in the same manner 

 as with the lower animals. But the several considerations 

 just referred to may be conveniently deferred for a time ; 

 and we will first see how far the bodily structure of man 

 shows traces, more or less plain, of his descent from some 

 lower form. In the two succeeding chapters the mental 

 powers of man, in comparison with those of the lower 

 animals, will be considered. 



The Bodily Structure of 3Ian. — It is notorious that 

 man is constructed on the same general type or model 

 with other mammals. All the bones in his skeleton can 

 be compared with corresponding bones in a monkey, bat, 

 or seal. So it is with his muscles, nerves, blood-vessels, 

 and internal viscera. The brain, the most important of 

 all the organs, follows the same law, as shown by Huxley 

 and other anatomists. Bischoff, 1 who is a hostile witness, 

 admits that every chief fissure and fold in the brain of 



' Grosshirnwindungen des Menchen,' 1868, s. 96. 



