342 Journal of Comparative Neurology. 



neuroglia, which surrounds on the upper, anterior and lower 

 sides a mass of small cells, which occupy the central and 

 posterior part of the lobe. * * * 



" The cells of the central group are small in size, re- 

 sembling to a certain extent those of the cerebrum. Many 

 are oval or circular in outline, but generally they are more or 

 less pear-shaped. Each cell has a nucleus of comparatively 

 large size, which is invariably situated at the broader end of 

 the cell; the protoplasm or cell-contents occupy the narrower 

 side, which terminates in a more or less blunt point, from 

 which a single free fibril emerges. The nucleus contains a 

 single spot-like nucleolus, situated near the centre, which 

 occasionally shows symptoms of breaking up into its con- 

 stituent granules. The total average length of these cells is 

 0.007 i"nillim. or 0.008 millim., their diameter 0.004—0.005 

 millim.; the nuclei are generally round, or nearly so, and 

 their diameter averages 0.004 I'nillim. 



"Many of these cells occupy spaces in the neuroglia 

 which probably correspond to the spaces surrounding the cells 

 of the cerebrum described by Obersteiner and Bevan Lewis. 

 Occasionally nearly the whole of the cell projects into this 

 chamber, but more generally only the broad end, so that the 

 nucleus alone would be bathed in lymph in the latter case. 

 The granules, which to a great extent compose the neuroglia 

 of the olfactory lobes, become aggregated together and form 

 a smooth surface on the walls of these spaces; they do not 

 actually form an epithelial layer, but seem to be a rudi- 

 mentary form of that structure. 



" A layer of neuroglia surrounds this group of cells, as 

 before mentioned, on all sides except posteriorly, in which 

 with high powers only very fine granules are to be observed. 

 The above described cells occur very sparingly here. 



" The external portion of the lobule is formed principally 

 by the fibres of the olfactory nerve. These fibres enter at 

 the anterior end, and occupy about half the length of the 

 lobe; they do not go straight, but the bundle, dividing at the 



