cxl NERVOUS SYSTEM. 



often finely branched, from their circumference (figs. LXXVIII and LXXIX); 

 and then they are often named, according to the number of processes they 

 present, uni-, bi-, and multipolar ; terms obviously ill chosen, but rendered 



Fig. LXXIX. 



Fig. LXXIX. NERVE-CELLS FROM THE CORTICAL GREY MATTER OP THE CEREBELLUM. 

 MAGNIFIED 260 DIAMETERS (from Kolliker, reduced). 



current by use. They have each, as a rule, a large, well-defined, clear, 

 round nucleus, and within this an equally distinct nucleoltis, or sometimes 

 more than one. The substance of the cell is soft and translucent, but finely 

 granular or punctuated, and slightly tinged throughout with a brownish red 

 colour ; and cells are often seen, especially those of the large ramified kind, 

 with one, or sometimes two, much deeper coloured brown patches, caused 

 by groups of pigment granules ; the colour is deeper in adult age than in 

 infancy. 



The bodies in question, although they still are commonly called " cells/' 

 appear to be destitute of a proper cell-wall. In the ganglia, it is true, they 

 are enclosed in a distinct capsule ; but this is probably adventitious, and 

 pertaining to the connective structure in which they are lodged. The out- 

 runners or branches are formed by prolongations of the same soft substance 

 which forms the cell-body ; they are, therefore, very readily broken, and 

 the cells thereby mutilated, in the manipulation required for their insulation. 



Various recent observers describe a faint striation, or a very fine fibrillation, in the 

 branched cells; the lines or fibrils are said to run along the outrunners, and also to 

 pass continuously through the body of the cell from one branch to another ; it is 

 further alleged by one writer (Frommann), that bundles of filaments proceed from the 

 nucleus and pass out of the cell at various points, in each of which bundles there is one 

 fibril connected with the nucleolus. 



Other nerve-cells (fig. LXXX, a) are found in the nervous substance, which 

 are distinguished chiefly by the pellucid, colourless, and homogeneous aspect 

 of the matter contained in them ; such cells possess a nucleus like the rest ; 

 they are seldom large, and have usually a simple round or oval figure. They 

 occur along with nerve-cells of the kind before described. Lastly, small 

 bodies of the size of human blood-corpuscles and upwards, containing one 

 or more bright specks like nucleoli, abound in the grey matter in certain 

 situations (fig. LXXX, 6, c). These bodies, which are sometimes called 

 "granules" (Korner in German), resemble the nuclei of nerve-cells; and 

 it may be a question whether they are not the nuclei of cells in which the 



