CORTICAL CELL LAMIXATIOX OF TAl'IO HAMADRYAS. 639 



The description given above applies in its details only to 

 the middle temporal gyrus. The cortex of the superior 

 temporal gyrus differs in many respects. It is broader and 

 poorer in cells. The lamina grannlaris interna is not so well 

 developed. The lamina ganglionaris is, on the whole, not so 

 clear, but contains a few large cells scattered through it. 



A change in structure is also apparent as one moves round 

 the temporal lobe in the other direction. As one approaches 

 the hippocampal gyrus the cortex becomes narrower, and the 

 layer of granules less well developed. 



The extent of the olfactory cortex is shown in fig. c, but it 

 has not been thought necessary to give a special description 

 or drawing of its structure. 



Anterior Limbic Cortex (fig. 12j. 



o Q ci a □ a CO 

 c3 a c:^ ^^ a a rj 



cncZi cii T=i en a c3 



The anterior limbic type is illustrated in fig. 12, which is 

 taken from the mesial surface of the hemisphere jusC above 

 the anterior portion of the corpus callosum. The cortex here 

 reaches a depth of TO mm. Its chief characteristic is the 

 absence of any very definite system of stratification. The 

 lamina granularis externa is very poorly developed ; it passes 

 gradually into the lamina zonahs above it and is hardly 

 possible to separate from the lamina pyramidalis below. The 

 latter is somewhat sparsely populated with small and medium- 

 sized pyramids until a depth of '6 or "7 mm. is reached ; below 

 this, extending for about half a millimetre, is a zone of cells 

 considerably larger in size and more closely arranged, which 

 probably represents the lower part of the lamina pyramidalis 

 (iii h) and the lamina ganglionaris (v). There is no trace of 

 the lamina granularis interna. The lamina multiformis is 

 also poor in cells, of which the upper ones are of fair size and 

 triangular form, while the lower ones are smaller and more 

 spindle-shaped. 



