738 DR JAMES W. DAWSON ON 



general outline of the borders of these processes (fig. 384). Such cells are found very abundantly in the 

 cerebral white matter and in the deepest layer of the cortex. 



Plate LXXIII. 



Figs. 385-396. Changes in cortical areas. 



Fig. 385, x 60. Demyelination of cortex without any change in the cyto-architecture. 



Fig. 386, x 45. Demyelination of cortex with marked glia cell reaction in the transition zone and 

 in the deep layers of the cortex. 



Fig. 387, x 60. Ditto. Note the marked alteration in the Betz cells (a). Figs. 385-357, Van 

 Gieson's stain. 



Fig. 388, x 80. Cortical and subcortical area with glia cell reaction in the deep layers of the cortex. 



Fig. 389, x 200. Transition zone, a = glia cells; c = fat granule cells. 



Fig. 390, x 200. Transition zone ; stage of advancing sclerosis, a = glia nuclei ; i = glia reticulum. 



Figs. 391-396. Glia cell changes in the respective layers of the cortex ; ef. figs. 21 and 22. a = pro- 

 liferated glia cells with numerous fibrils ; b = nests of small glia cells, around the ghosts of ganglion cells; 

 c = ganglion cells ; d = persistent axis cylinders ; e = blood-vessels. Note relation of the glia cell processes 

 and fibrils to the capillary walls. 



Fig. 391, x 200, and fig. 394, x 600. In the polymorphous (deepest) layer. Methyl-violet. 



Fig. 392, x 200, and fig. 395, x 600. In the layer of the deep pyramids. Methyl-violet. 



Fig. 393, x 200. In the granular layer; nests of small glia cells around ganglion cells or replacing 

 them. Hsematoxylin and eosin. 



Fig. 394, x 400. In the layer of the large pyramids. Note ganglion cells (c) surrounded by enlarging 

 satellite cells (/), whose protoplasm is filled with black-stained granules. Marchi method. Similar cells are 

 found around the capillary vessels in this layer. 



Plate LXXIV. 



Figs. 397-442. Low-power view of areas in myelin sheath and glia stains to show comparative 

 negative and positive pictures. 



Fig. 397, x 40, and fig. 400, x 30. Areas in the central white matter showing absence of myelin. 



Fig. 398, x 60, and fig. 401, x 30. Similar areas to show presence of glia in the demyelinated tissue. 



Fig. 399, x 50. Very minute area in the central white matter showing slight demyelination. 



Fig. 402, x 200. Similar minute area to show the commencing enlargement of the glia cells (a) in 

 this area of slight demyelination. 



Figs. 403-405. Transition peripheral zones in areas in the central white matter to show the glia nuclear 

 proliferation. Van Gieson's stain. Fig. 403, x 40, an old area with zone of small glia cells (b) ; fig. 404, 

 x 200, sclerosis still incomplete with large (a) and small (b) glia cells ; fig. 405, x 60, wedge-shaped zone 

 of small glia cells (b). 



Figs. 406-408. Transition zones of advancing areas in the spinal cord to show the mode of degenera- 

 tion of the myelin. Frozen sections ; Heidenhain's iron-hsematoxylin. Fig. 406, x 60, longitudinal 

 myelinated fibres passing into an "early" area; fig. 407, x 300, similar fibres under H.P. to show the fine 

 globules and droplets of myelin which take the hsematoxylin stain ; fig. 408, x 300, similar nerve fibres 

 in transverse section. 



Plate LXXV. 



Figs. 409-419. Ganglion cell changes in the anterior horn of the spinal cord (except fig. 418) (pp. 607, 

 808). Figs. 409-413, changes probably not related to the sclerotic process, but to the accompanying want of 

 function, decubitus, etc. ; figs. 414-419, changes probably related to both processes. 



Fig. 409, x 40. Ganglia cells very atrophic, but rounded forms present with nucleus and chromophile 

 granules almost normal in structure and arrangement. Figs. 409-411, polychrome methylene blue. 



Fig. 410, x 80. Similar cells occurring in a demyelinated area. 



