THE LAW OF EVOLUTION CONTINUED. 351 



knowledge of past life upon the Earth, is too scanty to justify 

 us in asserting an evolution of the simple into the complex, 

 either in individual forms or in the aggregate of forms; yet 

 the knowledge we have, not only consists with the belief 

 that there has been such an evolution, but rather supports it 

 than otherwise. 



§121. Whether an advance from the homogeneous to 

 the heterogeneous is or is not displayed in the biological 

 history of the globe, it is clearly enough displayed in the 

 progress of the latest and most heterogeneous creature — 

 Man. It is alike true that, during the period in which the 

 Earth has been peopled, the human organism has grown 

 more heterogeneous among the civilized divisions of the spe- 

 cies; and that the species, as a whole, has been made more 

 heterogeneous by the multiplication of races and the differ- 

 entiation of these races from each other. In 

 proof of the first of these positions, we may cite the fact that, 

 in the relative development of the limbs, the civilized man 

 departs more widely from the general type of the placental 

 mammalia, than do the lower human races. Though often 

 possessing well-developed body and arms, the Papuan has 

 extremely small legs : thus reminding us of the quadrumana, 

 in which there is no great contrast in size between the hind 

 and fore limbs. But in the European, the greater length 

 and massiveness of the legs has become very marked — the 

 fore and hind limbs are relatively more heterogeneous. 

 Again, the greater ratio which the cranial bones bear to the 

 facial bones, illustrates the same truth. Among the verte- 

 brata in general, evolution is marked by an increasing het- 

 erogeneity in the vertebral column, and more especially 

 in the segments constituting the skull: the higher forms 

 being distinguished by the relatively larger size of the bones 

 which cover the brain, and the relatively smaller size of 

 those which form the jaws, &c. Now, this characteristic, 

 which is stronger in Man than in any other creature, is 



