NO. 4 NERVOUS SYSTEM OF A CENTIPEDE — LORENZO 43 



Plate 5 



Fig. a. Showing the three types of nuclei {a, b, c,) found in the inner cellular 

 perilemmal portion of the neurilemma. A portion of a tracheole (tr) is seen 

 to the left with its small nucleus (out of focus) adhering to the periphery. 



Fig. B. The two types of neuroglial nuclei in the neuropile. One type (pn) 

 has pink staining chromatin with an exocentric nucleolus; tlie other (bn) has 

 densely aggregated black staining chromatin. The dimensions of the first type 

 may serve as a scale for this and the preceding figure (3x5 microns). 



Fig. C. a transverse section through a giant cell located in the subesophageal 

 ganglion. The large nucleus possesses a centrally situated clump of chroma- 

 tin (gen). A tracheole (tr) which may be mistaken for a second giant cell 

 process is seen to the left of the axon (ax). The mass of material ventral 

 to the nucleus (sp) may be a secretory product of the giant cell. The dimen- 

 sions of the nucleus are approximately 12 x 20 microns. 



