404 
Proceedings of the Royal Society of Edinburgh. [Sess. 
4. A broad zone composed of cells more or less pyramidal in shape ; 
among them lie some larger and more prominent cells, distinctly pyramidal 
in shape and measuring some 15 to 25 /j, in length by 10 to 15 jj. broad. 
r * , * * ' - * 
4 ^ * 
Z % 
% ** ® £ 'W* 
* © I‘ 
# B ^ 
*. *V * - • * 
* * v? £ - 
X** *«f ^ ? - 
9 ' 
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i*“ 9 * *• 
^ V ^ a <» A ^ 
Fig. 3. — Type I. x 100. 
From comparisons made between them and the cells forming a prominent 
feature in the fourth and fifth zones of the second type of cortex, it is 
evident that they are similar. Their significance will be discussed in the 
description of the second type. 
5. A broad polymorphic zone. 
(See fig. 3.) 
