vi ] Tapes of Cell Lamination- 155 



number may be gained from the statement that every transverse mm. of substance contains 

 from 8 to 12; the position they prefer is the immediate neighbourhood of the layer of 

 stellate cells, but they may be found nearer the surface and occasionally they lie within or 

 even below the stellate lamina: they measure from 45 to 50 p. in length by from 25 to 

 40 /j, in breadth; their form varies, at times being pyramidal, at other times stellate, and the 

 majority are a cross between the two ; they possess a stout apical process which, however, 

 often proceeds obliquely towards the surface ; their basilar dendrons are also stout, and 

 there may be more than two, and it is not uncommon to see dendrons issuing from well 

 up the side of the cell-body; the axon is usually found on the basilar surface. The pro- 

 toplasm of the cell contains large chromophilic particles : these are separated from one 

 another by distinct intervals, but all the same they impart a general depth of coloration to 

 the body which is greater than that of other large temporal cells. Relative to the general 

 size of the cells the nucleus is small. The position occupied by these cells is indicated 

 in figure 1.5 by the shaded (audito-sensory) area. The other large pyramidal cells possess 

 the same characters as those in other parts of the temporal lobe, but the presence of 

 abundant small pyramidal cells dotted about at this level seems peculiar to the area. 



The layer of stellate cells is approximately '30 mm. in depth, the component cells are 

 divided into columns by the radiary fasciculi, and they occur in such numbers that the 

 band forms a very prominent object. 



It is rather curious that no distinct internal lamina of large pyramidal cells is to be 

 made out in this cortex ; in the position which they should occupy only a few pale-stained 

 but fairly large cells are visible. 



The layer of fusiform cells is deep (quite 1 mm.) and richly-stocked, but the 

 arrangement differs from that in other parts in being distinctly less columnar, and also 

 the processes of the individual elements point in all directions instead of uniformly up and 

 down. This appearance is no doubt attributable to the confused arrangement of nerve fibres 

 in the same situation. Xo large cells, corresponding to the solitary cells of Meynert in 

 the visual area, are found in the depths of the cortex. 



From the foregoing it may be gathered that the leading features of this type of cortex . 

 are (I) the general rich supply of cells, and (2) the presence of numbers of curious giant 

 cells above the well-developed stellate layer: and I may here say in regard to distribution 

 that it corresponds exactly with the area mapped out by fibre-arrangement. 



SUPERIOR TEMPORAL CONVOLUTION. TYPE No. 2 (Plate XV, fig. 2). 



Over that part of the crown and lower wall of the superior temporal convolution, which 

 constitutes the second field of special fibre-arrangement, the following cell lamination obtains 

 and as closely marks its external limits. 



The plexiform layer is similar to that in the transverse temporal gyri. 



The layer of small pyramidal cells may be a trifle deeper but does not seem to be 

 so densely packed with cells. 



The pyramidal cells of medium size are also not so numerous and the combined depth 

 of this and the giant cell layer is less. 



202 



