ilAND. — Nerve-Cell Oentrosome. 



PLATE 6. 



All the figures magnified 2000 diameters. 



Fig. 38. Young cell (with several of the neighboring nuclei) from the anterior end 

 of a cord of 34 days' regeneration. Iron-haematoxylin. 



Fig. 39. Small cells with resting nuclei from the anterior end of a cord of -34 days' 

 regeneration. Each of the two cells has a centrosome. Iron-haema- 

 toxylin. 



Fig. 40. Cell with a greater mass of cytoplasm than in the cells of Figure 39 ; 

 centrosome and radiations. From a brain of 34 days' regeneration. 

 Iron-hsematoxylin. 



Fig. 41. Cell, similar to that of Figure 40, from a brain of 37 days' regeneration ; 

 centrosome and radiations. Iron-haematoxylin. 



Fig. 42. Three cells from the anterior end of a cord of 34 days' regeneration. A 

 centrosome witli radiations may be seen near each of the two larger 

 nuclei, on the side toward the greatest cytoplasmic mass. Iron-haema- 

 toxylin. 



Fig. 43. Two cells from the epidermis of a normal worm. The centrosome is at the 

 deeper end of each nucleus. Iron-haematoxylin. 



Figs. 44, 45. Cells from regenerated epidermis, showing centrosomes and radia- 

 tions. 16 days' regeneration. Acetic-sublimate, Kernschwartz and 

 safranin. 



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