176 NATURAL HISTORY OF 



inal pair, there appear immediately two others int< rmediate 

 between them, possessing the modified combination of chaiac- 



ters of two of the foregoing, sufficiently remote from both to 

 seem deserving, likewise, the denomination of Bpecies, or at 

 least of normal varieties, if it were not that the same difficulty 



obtrudes itself between every succeeding intermediate aber- 

 rance. Hence, from the time of LinnSBUS, who tared 

 to place Man in the class Mammalia, systematise hav< 



various diagnoses for separating tin.' different types or varieties 

 of the human family ; such as, the form of the skull, the facial 

 angle, the character of the hair, and of the mucous membrane. 

 But the skeleton and internal structure may not have been suf- 

 ficiently examined in all conditions of existence. 



It does not appear that a thorough research has yet been 

 made in the successive cerebral appearances of the foetus, nor 

 of the character the brain of infants exhibits, immediately after 

 parturition, in each of the three typical forms. M. de Serres, 

 indeed, has led the way, and already, according to him, most 

 important discoveries have resulted from his investigations ; 

 for, should the conditions of cerebral progress be more complete 

 at birth in the Caucasian type, as his discoveries indicate, and 

 be successively lower in the Mongolic and intermediate Malay 

 and American, with the woolly-haired least developed of all, it 

 would follow, according to the apparently general law of pro- 

 gression in animated nature, that both — or at least the last 

 mentioned — would be in the conditions which show a more 

 ancient date of existence than the other, notwithstanding that 

 both this and the Mongolic are so constituted that the spark of 

 mental development can be received by them through contact 

 with the higher Caucasian innervation; thus appearing, in 

 classified zoology, to constitute perhaps three species, originat- 

 ing at different epochs, or simultaneously in separate regions, 

 while by the faculty of fusion with the last or Caucasian, im- 

 parted to them, progression np to intellectual equality would 

 manifest essential unity, and render all alike responsible beings, 



