THE HUMAN SPECIES. 177 



according to the degree of their existing capabilities — for this 

 mast be the ultimate condition for which Man is created. Fan- 

 ciful though these speculations may appear, they seem to confer 

 more harmony upon the conflicting phenomena surrounding 

 the question, than any other hypothesis that rests upon physi- 

 ology, combined with geological data and known historical 

 facts.* 



*The higher order of animals, according to the investigations of 31. de 

 Serres, passes successively through the state of inferior animals, as it were 

 in transitu, adopting the characteristics that are permanently imprinted 

 on those below them in the scale of organization. Thus, the brain of 

 Man excels that of any Other animal in complexity of organization and 

 fulness of development. Eut this is only attained by gradual steps. At 

 the carlirst period that it is cognizable to the senses, it appears a simple 

 fold of nervous matter, with difficulty distinguishable into three parts, 

 and having a little tail-like prolongation, which indicates the spinal mar- 

 row. In this state it perfectly resembles the brain of an adult lisli ; thus 

 assuming, in transitu, the form that is permanent in fish. Shortly after, 

 the structure becomes more complex, the parts more distinct, the spinal 

 marrow better marked. It is now the brain of a reptile. The change 

 continues by a singular motion. The corpora quailrigcmina, which had 

 hitherto appeared on the upper surface, now pass towards the lower ; the 

 former is their permanent situation in fishes and reptiles, the latter in 

 birds and mammalia. This is another step in the scale. The complica- 

 tion increases ; cavities or ventricles are formed, which do not exist in 

 either fishes, reptiles, or birds. Curiously organized parts, such as the 

 corpora striata, are added. It is now the brain of mammalia. Its last 

 and final change is wanting, that which shall render it the brain of 3Ian, 

 in the structure of its full and human development. But although, in this 

 progressive augmentation of organized parts, the full complement of the 

 human brain is thus attained, the Caucasian form of Man has still other 

 transitions to undergo, before the complete chef (V&uvre of nature is per- 

 fected. Thus, the human brain successively assumes the form of the 

 Negroes, the 3Ialays, the Americans, and the Mongolians, before it attains 

 the Caucasian. Nay, more, the face partakes of these alterations. One 

 of t ,e earliest points where ossification commences is the lower jaw. 

 This bone is therefore sooner completed than any other of the head, and 

 acquires a predominance which it never loses in the Negro. During the 

 soft pliant state of the bones of the skull, the oblong form which they nat- 

 urally assume approaches nearly the permanent shape of the American. 

 At birth, the flattened face and broad smooth forehead of the infant ; the 



