752 



always be distinguished by its stout appearance, which is directed 

 upwards toward the central regions of the brain, where it terminates, 

 either by a gradual process of attenuation, or by ending in a cone- 

 shaped figure. 



Along the borders of the optic nerves, and among their fibres, 

 the neuroglia cells return to the long rayed Golgi type, but their 

 processes are of far thicker calibre and coarsely but infrequently 

 beaded, visible much longer distances among the nerve structures, 

 than the ordinary long rayed cells, the two forms being drawn for 

 contrast in figures 2 and 3. 



Sixty to eighty mikrons above the floor of the brain, we first 

 find most interesting transition forms between those cells already 

 described, and others of probably later development. In no. 12 of 

 the main drawing, we find an illustration of an irregular cell with 

 quite large body and numberless rays of considerable length, extend- 

 ing in all directions from it. These processes are further sub-divided 

 into shorter and longer rays of non-branching character; and shorter 

 stout rays with a few short branches, both processes and their branches 

 being covered with minute hair-like projections, giving the arms a 

 shaggy appearance. On the opposite side of the drawing, a smaller 

 cell is depicted (fig. 1, no. 13), of the same general character, but 

 with few smooth processes of any length, often baaring at their ter- 

 minations globular figures. The other extensions of the cell are short 

 and thick, and are covered with the same fuzzy hairs. 



Very numerous forms of similar cells are present all through this 

 region, and finally, higher up, give place to the long rayed Golgi 

 cells, intermingled with a few of the short armed variety. 



It is at times almost impossible to distinguish between these 

 hairy cells and some of the smaller varieties of nerve cells lying in 

 the circumjacent regions. On the left side of the drawing (no. 15), 

 the same hairy appearance of the body and main arms of the cell 

 may be noticed, also the globular endings to the processes directed 

 downwards, and when the neuron of the nerve cell is not stained, it 

 is utterly impossible to differentiate between these varieties of nerve 

 and similar shaped neuroglia cells. 



The last variety of glia cell (fig. 1, nos. 14), that is present along 

 the borders of the ventricle, though never nearer than 50 to 80 (i 

 from it, and never very near to the base of the brain, is a cell with 

 a body of variable size as well as irregular shape. Extending from 

 the protoplasmic body are a variable number of stout prolongations, 

 and these extensions, as well as the body of the cell itself are covered 



