Linihir Lobe and Olfactory Area 



vn] L'nnlnc Lobe ami ()l factor// Area IS? 



As ti> tlu- nucleus it is of small size, and its outline is obscured by the general intense and 

 diffuse coloration of the cell plasma. 



FIG. 19. Showing some of the deeply stained pregenual cells of the liinbic cortex. 



Distribution of the above-described Chromophilous Cells. 



Being so very different from any other cells on this surface of the frontal lobe it is 

 easily possible to map out their particular area of occupation. (Plate I, Limbic B.) The 

 field is entirely confined to the gyrus fornicatus; curving round the genu in the form of a 

 strip 5 to 10 ram. broad, it tails off posteriorly and ceases above the middle of the convexity 

 of the coqjus callosum. Below the rostrum and in front of the genu it comes into contact 

 anteriorly with the prefrontal area ; in this brain the mid-limbic division of the calloso- 

 marginal sulcus forms a rough boundary, and it is to be noticed that in the upper three- 

 fourths of its extent the strip is separated from the apposed prefrontal and frontal areas by a 

 buffer of cortex showing the general limbic type of arrangement. Lastly, I would emphasise 

 the point that its relation to the corpus callosum appears to be more important and 

 constant than that which it bears to any of the sulci on the mesial surface of the frontal 

 lobe, I would also give it as my belief that it owes its position to the growth of the 

 cor] ins callosum, and that at an early period of development it forms a part of the deposit 

 which is used in the construction of at any rate the anterior portion of the hippocampus, 



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