SCIENCE. 



175 



the centres have been localized in regions homologous to 

 those of the dog, and in which, furthermore, the archi- 

 tecture of the cortical surface is fundamentally the same, 

 I proceeded to review the question of the localization of 

 the giant-cells. 



On the one hand, Betz seemed to argue that the giant- 

 cells, which he claims to have discovered, were motor, 

 because they were found at those points in the dog's 

 brain where Hitzig and Fritsche, by supposed localized 

 electrization, had produced contractions of special groups 

 of muscles. Again, on the other hand, it is apparent 

 that those interested in defending that narrow localiza- 

 tion theory, which is such a prominent feature in the 

 teachings of Charcot and Ferrier, have found one of their 

 strongest supports in the anatomical discoveries of Betz. 



Let us suppose then, for the sake of argument, that it 

 be granted that larger cells mean motor centres for larger 

 muscles ; taking up the localizationists on their own 

 ground we will examine the location of these giant-cells 

 in a cat's brain, which only differs in a single exception 

 from the dog's, and is therefore a fit subject for study. 

 In fact, the cat's brain has the advantage of being some- 

 what simpler. 



The results I have obtained are based upon the study 

 of the cortical area of the two hemispheres of one cat. 

 One hemisphere was cut as a whole into some seventy- 

 five sections, from different altitudes transversely to the 

 cerebral axis. The other was separated into eleven seg- 

 ments, and each segment cut into a number of thin sec- 

 tions. The series of sections derived from the first 

 hemisphere served as a sort of topographical guide for 

 the location of anything that might be found in the sec- 

 ond. 



I found that th; giant-cells are not confined to localized 

 areas as B=tz claims. I find that thev are not as numer- 

 ous near the sulcus cruciatus as they are much posterior 

 to that region. I have even found giant-cells not very 

 far from the base of the brain, but I found the largest 

 group of the largest cells in a place not yet indicated on 

 any of the charts of the localizationists as an unquestion- 

 able motor point. In the accompanying woodcut the posi- 

 tion of the nest of cells that I have discovered is accur- 

 ately demonstrated. These cells are ovoid, circular, and 



sub-pyramidal in shape, and possess a round nucleolated 

 nucleus situated about the centre of the cell. Each cell 

 has from two to six visible processes. The ovoid cells are 

 much the larger, their long diameter measuring from 

 0.08 mm. to 0.12 mm.; and their short diameter from 

 0.05 mm. to 0.06 mm. The circular and subpytamidal 

 cells measure from 0.07 mm. to 0.08 mm. in diameter. 

 The nuclei of all the varieties are of the same size, and 

 measure 0.03 mm. in diameter. 1 only succeeded in finding 

 them in one locality, but found them very numerous in that 

 area. They are situated in the first primary arched 

 gyrus, between the Sylvian and anterior Sylvian fissures. 

 Ferrier, in his " Functions of the Brain " indicates a 

 " centre " on the frontal division of the fourth external 

 convolution, where, he says, he has observed, on irritat- 

 ing this centre, " a divergence of the lips so as to par- 

 tially open the mouth." This centre approaches nearer 

 in position to the one I have discovered than any other. 

 With this study I was enabled to locate the chief foci for 

 condensation of the giant-cells, of the shape known to 

 Betz and Mierzejewski. These are pyramidal in shape, 

 with a central round nucleus, and measure from 0.09 

 mm. to 0.12 mm. in length, and from 0.03 mm. too.04 mm. 

 in width at the base. Their nuclei measure 0.02 mm. in 

 diameter. The following woodcut shows how 

 two of Betz's largest cells can be placed so that their 

 conjoined areas are only equal to the areas of one of the 

 ovoid cells such as I have described. 



I regard the term " aiea of large cells " as inaccurate. 

 The large cells are scattered more or less widely over the 

 brain-surface, and it would be better to speak of " foci " 

 when they are concentrated in larger numbers than else- 

 where. 



The giant-cell of Betz is not a new discovery. It is not 

 a thing by itself distinct from the other pyramidal cells 

 of the cortex. On the contrary, both in the human cor- 



tex and in the cat, every transition from the average- 

 sized cell of the third frontal layer to the giant-cell can 

 be traced. I would also call attention to the fact that 

 Betz states " these cells to be in nests " and not uni- 

 formly distributed in one layer, but I have seen, in one 

 section from the paracentral lobule of the human brain, 

 giant- cells arranged in regular order like soldiers on 

 parade, for a distance of one-third of an inch. 



Taking the deductions, which have been based upon 

 the existence of these cells, on their merits, we find that 

 those who have relied on this demonstration for the sup- 

 port of the theory of motor centres, are reduced to a 

 number of predicaments. 1. That the largest giant-cells 

 have been found in the brain of carnivora where no 

 motor centre has been clearly demonstrated, and near 

 which only small muscles are supposedto receive their cor- 

 tical innervation. 2. That if, after all, this is a motor 

 centre, that the methcd of localization was incompetent 

 to detect it. I have limited myself this evening to this 

 single fact. I need not say that the giant-cell was known 

 to Meynert, although its locality was not accurately de- 

 scribed by him. He claimed that the larger gyri of the 

 frontal lobe contained the largest cells. On the other 

 hand, cells as large as the giant-cells can be seen through 

 the entire occipital lobe, according to this observer, in 



