430 Miscellaneous. 



With regard to the use of the structure of the brain as a character 

 for systematic division, the author is decidedly of opinion that it will 

 prove to be of no greater value than other isolated characters, like 

 those used by Miiller and Agassiz for the classification of fishes. 

 He says that every single character, even when it appears to be- 

 constant for long series of animals, suddenly proves to be deficient, 

 leaving wide gaps, forcing us to make exceptions, and thereby de- 

 stroying the necessary generality. It is the mutual relation of the 

 single organs to one another, the structure of the single parts and 

 elements in their combination, which must guide us in our systematic 

 attempts, rather than the presence of very subordinate internal or 

 external peculiarities of a single organ. There is much that is in- 

 genious and worthy of consideration in Owen's attempt to use the 

 convolutions of the brain, &c, for the classification of Mammals : 

 and we might perhaps expect, from the importance of the organ, 

 to obtain from it general relations, the fluctuations of which in sub- 

 ordinate characters may be more easily explicable. 



In the special examination of the convolutions, it will always stand 

 as a strange fact, that animals so highly organized and having so 

 high a psychological development as Birds, have the surface of the 

 hemispheres smooth and without folds, like mammals of low organi- 

 zation. Even in Man, moreover, the fact of the existence of a great 

 number of folds in very intellectual individuals is not without excep- 

 tions. 



On the other hand, it is true that the typical arrangement of the 

 convolutions and the formation and structure of the individual lobes 

 of the cerebrum are in intimate connexion with the groups, orders, 

 and families of our system, and that only those animals which 

 belong to one natural group can be compared with one another 

 with regard to the higher or lower development, arrangement of 

 lobes, and number and course of the convolutions. Considering 

 this, we are compelled to say that, in a broad sense, Man must 

 be placed in one and the same group with the Quadrumana as 

 regards the structure of his brain, but in a narrower sense, that he 

 forms a separate group by himself. This applies to the structural 

 ensemble of the arrangement of the brain, the stages of develop- 

 ment, and the configuration of the principal convolutions ; but it is 

 difficult to see how relatively very unimportant parts of the brain, 

 which are subject to great variations even in single human indivi- 

 duals {e. (/. the shorter or longer cornua posteriora ventriculi late- 

 ralis, the presence of a pes hippocampi minor, simple or double emi- 

 nentice candicantes), can be brought forward as more or less essen- 

 tial characters of the human brain, distinguishing it from that of the 

 anthropoid Apes. There is not only a striking similarity between 

 both in the whole of their external appearance, but this similarity 

 also extends to the different stages of development of the human 

 brain, if we compare them with the different forms of the lower-or- 

 ganized small Monkeys and of the highly developed anthropoid 

 Apes. 



The author, finally, confirms Gratiolet's observation, that the brain 



