Ill] Ti/jn of ('<// Ldniiiiutinn 31 



As the histology of these cells li.-is been described with perfect accuracy .-mil in full detail 

 by nmiKTous nthei- workers, and. since every neurologist is familiar with their appearances, I 

 need only shortly recapitulate pre\ ions observations and men!, ion that their size exceeds that 

 of any other cells to he met with in the whole cerebral cortex; that the word "p\riform" best 

 describes their shape; that they throw off a number of stout lateral and basal processes and 

 hence are deserving of the name " multipolar." which has been applied to them; that their 

 main apical dendron can be traced vertically upwards to the first layer, while their axis 

 cylinder drops directly into the white substance; that the cell body contains abundant large 

 masses of chromophilic material (Nissl bodies); and that the nucleus which is oval in shape 

 is, on comparison with that of other cells, small in proportion to the cell body. 



Leaving the distribution, arrangement and topical variations exhibited by Betz cells for 

 later consideration, I may lastly point out that this stratum is not occupied by such cells 

 alone, but that scattered about among them is a goodly number of large pyramidal cells, 

 similar to those seen overlying the rudimentary stellate layer. 



Lui/er a/ ^j)ii/<il<'-S/ii/j>t'(! Cells. 



This, the last layer, is an unimportant one and not worthy of special description : it 

 contains spindle-shaped, polymorphous, and triangular cells, similar to those met with in the 

 same layer in other regions. 



ARRANGEMENT, TOPICAL VARIATIONS AND DISTRIBUTION OF THE CELLS OF BETZ. 



It did not escape the observation of Betz, their original describer, that these giant cells 

 favoured a peculiar clustered arrangement, but in a paper by Bevan Lewis and Henry Clarke,- 

 published in the Transactions of the Royal Society in 1878, an account of the arrange- 

 ment of these bodies will lie found which lacks nothing in completeness and accuracy and 

 supplies many details which Betz did not touch upon. As a result of the examination of 

 the central convolutions of eight human brains, cut seriatim on a freezing microtome, these 

 two observers concluded that the cell clusters or nests could be further compressed into 

 groups, and these groups of nests were found to favour definite areas, areas the extent of 

 which did not vary very markedly in different brains. From their descriptions and diagrams 

 we gather that the areas were distributed in series over the precentral area as follows : one 

 occupied the "posterior two-thirds" of the paracentral lobule, and contained nests of enormous 

 cells ; a second and important group containing perfect and dense clusters of large cells was 

 situated at the broad upper extremity of the precentral gyrus, close to but without the 

 margin of the hemisphere, and was largely represented on the anterior wall of the Rolandic 

 fissure ; the third group lay more or less on the free surface of the precentral gyrus, opposite 

 the lower end of the base of the superior frontal gyrus; the next group seems to have been 

 placed immediately above the level of the genu ; and after this there came a barren area 

 (evidently on a level with the great annectant buttress pre\iously alluded to); the next group 

 lay immediatelv below the level of the upper genu, partly on the five surface and partly 

 within the Rolandic fissure, and was the last important group noticed, tor, although two others 

 are described opposite- the base of the middle frontal gyrus, they are said to be subject to 



