4 Transactions of (he 



their extensive ramificatious throughout the whole grey layer, to 

 terminate in its terminal network. Another much smaller process, 

 arising from a point opposite to the large process, passes into the 

 nucleated layer, and is transformed into a dark-bordered nerve 

 fibre. Distributed throughout the granular substance between the 

 extensive ramifications of the large ganglionic bodies of PurUnje, 

 a number of smaller ones of a triangular form is observed. From 

 their acutely projecting angles fine processes arise, which, however, 

 even in the most favourable cases, can be traced only to a very 

 short distance. Single free nuclei are also distributed throughout 

 the whole layer. In addition to the elements of the grey layer just 

 mentioned, there are a considerable number of fine nervous fibrillae, 

 which, arising directly from the terminal network, pass over to the 

 nucleated layer, either singly or in the form of anastomoses. They 

 arise in all parts of the grey layer, and approach in a vertical direc- 

 tion its inner border. At the summit of the convolution they 

 penetrate in this direction into the neighbouring nucleated layer, 

 more or less parallel to the axis of the convolution. . At the sides of 

 the latter, however, they make a greater or smaller curve, before they 

 leave the grey layer, in order to pursue a course parallel to the axis. 

 The nucleated layer is a continuation of the grey layer. Its 

 examination is rendered difficult by a large number of nuclei 

 densely distributed through it, and preventing one from obtaining 

 a clear view of the relative arrangement of the axis cylinders and 

 nerve fibres passing through the interspaces. In examining a very 

 thin section at the summit of a convolution, it will be observed that 

 the granular substance of the grey layer extends through the whole 

 nucleated layer and even farther, and fills up the interspaces left 

 between the nuclei, fibrillae, and dark-bordered nerve fibres. There 

 will also be observed a number of fine nervous fibrillae, which, 

 singly crossing or anastomosing with each other, pass over from 

 the former to the latter. The greater portion of these fibrillae are 

 most probably derived from the terminal network of the grey 

 layer ; a small part of them, however, may arise from the smaller 

 gangUonic bodies, a conjecture which I have not been able to con- 

 firm by direct observation. But it is certain that a large part 

 of them originate in the network, not only in the gi-ey but also in 

 the nucleated layer. In extremely thin, somewhat torn sections, 

 especially at the border of the nucleated layer, the fibrillous 

 terminal network, passing through the granular substance, can 

 be distinctly recognized, as well as fine and short fibrillae arising 

 from it, which, after anastomosing with each other here and there, 

 finally unite to form fine axis cylinders. These are soon trans- 

 formed into dark-bordered nerve fibres, and after passing through 

 the nucleated layer, more or less parallel with the axis of the con- 

 volution, at last disappear in the white substance. 



