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THE NERVOUS SYSTEM 



acteristic element; and their perikarya are closely grouped together, forming 

 a well-defined layer (Fig. 208, C). The tufted cells are smaller and more super- 

 ficially placed (Fig. 208, B). The larger dendrites from both these types of' 

 neurons are directed toward the superficial fiber layer. Each of these dendrites 



Fig. 208. Section of the olfactory bulb of a kitten. Golgi method. A, Layer of glomeruli; 

 B, external plexiform layer; C, layer of mitral cells; D, internal plexiform layer; E, layer of granules 

 and white substance; /, J, granule cells; a, b, glomeruli, showing the terminations of the olfactory 

 nerve-fibers; c, glomerulus, showing the terminal arborization of a dendite of a mitral cell; d, 

 tufted cells; e, mitral cell; h, recurrent collateral from an axon of a mitral cell. (Cajal.) 



breaks up into many branches, which form a compact rounded bushy terminal. 

 The terminal ramifications of olfactory nerve-fibers interlace with these dendritic 

 branches, and the two together form a circumscribed, more or less spheric ol- 

 factory glomerulus (Fig. 208, A). These relations were demonstrated by Cajal 



