6 THE DESCENT OF MAN. 



severe struggles for existence; and consequently to beneficial vari- 

 ations, whether In body or mind, being preserved, and injurious 

 ones eliminated. Do the races or species of men, whichever term 

 may be applied, encroach on and replace one another, 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 an- 

 swered in the aflirmative, 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 succeeding chapters the 

 mental powers of man, in comparison with those of the lower 

 animals, will be considered. 



The Bodily Structure of Man.— It is notorious that man is con- 

 structed on the same general type or model as other mammals. 

 All the bones in his skeleton can be compared with correspond- 

 ing 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,^ who is a hostile witness, 

 admits that every chief fissure and fold in the brain of man has 

 its analogy in that of the orang; but he adds that at no period of 

 development do their brains perfectly agree; nor could perfect 

 agreement be expected, for otherwise their mental powers would 

 have been the same. Vulpian- remarks: "Les differences reelles 

 "qui existent entre I'encephale de I'homme et celui des singes 

 "superieurs, sont bien minimes. 11 ne faut pas se faire d'illusions 

 "a cet egard. L'homme est bien plus pres des singes anthropomor- 

 "phes par les caracteres anatomiques de son cerveau que ceux-ci 

 "ne le sont nonseulement des autres mammifSres, mais meme de 

 "certains quadrumanes, des guenons et des macaques." But it 

 would be superfluous here to give further details on the corre- 

 spondence between man and the higher mammals in the structure 

 of the brain and all other parts of the body. 



It may, however, be worth while to specify a few points, not 

 directly or obviously connected with structure, by which this 

 correspondence or relationship is well shown. 



Man is liable to receive from the lower animals, and to com- 

 municate to them, certain diseases, as hydrophobia, variola, the 



1 'Grosshirnwlndungen des Idenschen,' 1S68, s. 96. The conclusions of 

 this author, as well as those of Gratiolet and Aeby, concerning the 

 brain, will be discussed by Prof. Huxley In the Appendix alluded to in 

 the Preface to this edition. 



2 'Lee. sur la Phys.' 1866, p. 890, as quoted by M. Dally, 'L'Ordre des 

 Primates et le Transformlsme,' 1868, p. 29. 



