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portion of the hemisphere, the parieto-frontil lobe (a) is 

 made up of these kinesodic cells. 



The same lobe in sections further mesad is greatly re- 

 duced (Figs. 2 and 3, a), having been encroached upon by 

 a dense mass of the spherical bodies constituting the central 

 granular part of the olfactory lobe. This close approxima- 

 tion of the olfactory lobe upon the hemispheres has the effect 

 of apparently driving the frontal lobe ventrad, for there is a 

 small cluster of pyramidal cells at the point represented at 

 Fig. 4, c. Almost the entire dorsal surface also bears cells of 

 the kinesodic type. 



The cells of the occipital lobe, on the other hand, 

 have the spindle shape and large clear nuclei of the typical 

 jesthesodic cells. 



The olfactory bulbs are very large and are soldered 

 obliquely upon the front of the cerebrum and ventral ly are 

 fused with each other, producing an eftect not unlike that 

 seen in Rana. 



The histological structure is similar to that in the alliga- 

 tor. Externally, especially cephalad and ventrad, is the 

 area of convoluted olfactory fibres, each bundle being sepa- 

 rated from its neighbor by sheathing fibres richly filled with 

 dark elongate inoblastic nuclei and scattered oval Deiters' 

 corpuscles. Then follows the glomerary zone of gelatinous 

 aspect, in which almost the only cellular elements resemble 

 Deiters' nuclei. An intervening zone nearly devoid of cells 

 separates this from the cortex olfactorii proper, in which, 

 besides Deiter cells, there are two distinct elements: first, 

 large, irregularly-angular or fusiform cells, with clear gran- 

 ulated nuclei of large size; second, small, densely staining 

 multipolar cells such as we have elsewhere recognized as 

 characteristic of the prosencephalic olfactory regions. This 

 variety of cells is abundant, for example, along the ventral 

 surface of the cerebrum in rodents. The nuclei of these cells 

 are irregular and stain deeply. Separating this zone from 

 the medullary portion is a second layer nearly devoid of 



