1908.] Cell Lamination of Cerebral Cortex of the Lemur. 499 
layer measuring about 0°15 mm., the pyramidal layer about 0°8 mm., the 
granules 0°2 mm., the polymorph layer about 0°6 mm. in depth (vide fig. 8). 
The pyramidal cells are rather more numerous than in the motor area (A), 
and are not so large, and are more regularly arranged. At the bottom of the 
layer is a line of supra-granular pyramids which average about 7 w by 2 in 
size. The granule layer is well marked, and above it and among the 
granules are scattered a few stellate cells. They are not, however, so 
numerous as in the temporal and visual areas. The line of large infra- 
granular pyramidal cells is characteristic of this area. They are plump 
pyramidal-shaped cells, measuring on an average 35m by 15, having 
several branched processes and Nissl granules. These cells seem to 
correspond to similar cells described by Campbell as occurring in the post- 
central convolution in the primates. 
Temporal Area ou 
Extent and Boundaries.—The “ temporal type” covers the greater part of 
the temporal lobe. Inferiorly it extends to within about 4 mm. of the rhinal 
fissure, and there merges into type “R.” Anteriorly it extends on to the 
inferior wall of the Sylvian fissure and ends abruptly at the gyrus which 
lies at its base; the lamination on the other side of the sulcus being 
type “R” (vide fig. 3). Behind this gyrus the temporal type crosses the base 
of the Sylvian fissure, and gradually merges into the post-central type. 
Curving round the posterior extremities of the Sylvian fissure and the 
parallel sulcus, and covering the rudimentary sulci behind the latter, it again 
merges gradually into the cortex which is intermediate to it and the post- 
central and visual types respectively. On the-under surface the inferior 
occipital sulcus forms a boundary posteriorly, and more anteriorly it merges 
into an area which seems to be intermediate to it and the visual type. . 
Characteristics.—The depth of the cortex is about 2 mm., the molecular 
layer measuring about 0°15 mm., the pyramidal 0°7 mm., the granules 
0°25 mm., the zone in which the large infra-granular pyramids lie about: 
0-2 mm., and the polymorph layer about 0°7 mm. in depth (fig. 9). The 
superficial cells of the pyramidal layer are small and rather closely crowded 
together ; and among the more usual triangular cells may be seen a few which. 
are quadrilateral in shape. The remainder of the pyramidal layer is formed. 
of well developed pyramids, which are larger and less closely packed than. 
those of the visual area, and more regularly arranged than in the motor. 
The largest cells at the bottom of the layer measure about 30 by 7. The 
granule layer is conspicuous. The individual cells are larger and less 
