I08 HUNTER. [Vol. II. 



Fig. 5). In some specimens it was as much as three-fourths 

 of the cell diameter ; in others it was much smaller and less 

 pronounced. It is made up of the coarse granules of the periph- 

 eral part of the cell-body. Next is found a clearly staining 

 area, homogeneous or finely granular, which always contains 

 one, often several, black deep-staining granules, the centrosome 

 or central bodies of authors. This clear area corresponds to 

 the sphere of Von Lenhosseck or the disc of McClure. Such an 

 area may be of considerable size and contain visible radiations 

 which extend out into the surrounding cytoplasm (Miss Lewis), 

 or may be reduced so as to be almost or completely wanting 

 (see Fig. 5). The central bodies are of variable number. One 

 large granule is frequently found ; perhaps two is the most 

 constant number. This last statement seems especially true 

 for young cells. 



The above-described type of centrosome is often met with, 

 but there are many modifications. In some of the cells of a 

 ganglion may be found a centrosome with well-developed astral 

 rays, presenting the appearance found in leucocytes. In other 

 cells of the same ganglion (see Fig. 5) may be found a centro- 

 some with the typical archoplasmic condensation around it. In 

 still other cells the centrosome may have little or no conden- 

 sation of cytoplasm about it, and may exist as a deep-staining 

 granule in the cell. Again, such a centrosome as last men- 

 tioned may be made up of several granules which seem to be 

 more or less solidly welded together. All these forms or states 

 of centrosomic activity may be present in one or the same 

 section (see Fig. 5). This figure shows that the centrosome 

 structure is not a fixed one, such as Von Lenhosseck pictures, 

 but extremely variable in form, more so than Miss Lewis fig- 

 ures. It seems evident from this that the centrosome, as a 

 dynamic center, is of varying importance in different cells. 

 This is further shown by the differing amount of condensation 

 in other cells, as well as the manner in which the nucleus is 

 indented. In these cells, all described being from adult speci- 

 mens of varying age, we see represented various-sized cells. 

 There seems to be no restriction as to size, although the 

 centrosome is much easier to prove in the larger cells. 



