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NOTES UPON THE NATUEAL SUBDIVISION OF THE 

 CEEEBEAL HEMISPHEEE. By G. Elliot Smith, M.D., 

 Felloio of St John's College, Cambridge ; Professor of Anatomy, 

 Cairo, 



It is a peculiar fact, significant not only of the imperfections 

 of the current nomenclature, but even to a greater extent of 

 the unsatisfactory state of the present teaching in cerebral 

 morphology, that there is no term generally accepted or 

 acceptable among the multitude of names now employed in 

 Descriptive Anatomy which can be applied exclusively and 

 without confusion to the most characteristic and distinctive 

 feature of the mammalian brain ; to that part, in fact, which 

 is the dominant organ of the whole body, and in the more 

 highly placed Eutheria, constitutes the great bulk of the whole 

 nervous system. I refer to that area of the cerebral cortex, with 

 its associated medullary matter, which, in a series of earlier 

 memoirs,^ I have wrongly called the " palHum." But it is only 

 one of the three histological formations which constitute the 

 true pallium ; and, as it is the latest of these to reach the height 

 of its development, we may call it the " new pallium," or, if the 

 hybrid term be permissible, " neopallium," in contradistinction 

 to the " old pallium " of the Sauropsida and the earlier Yerte- 

 brata, which is cMefiy formed of the other two pallial areas. 



If a cerebral hemisphere of any mammal be submitted to 

 careful examination, it will be found to be composed of a 

 number of distinct regions, each of which exhibits well-defined 

 and unmistakable histological features peculiar to itself. I'hus 



1 See " The Brain in the Edentata," Trans. Linn. Soc, 2nd series,— Zoology, — 

 vol. vii., 1899, p. 324. - 



VOL. XXXV. (N.S. vol. XV.) — JULY 1901. 2 G 



