546 



NAOKI SUGITA 



Dating the areas shown in the maps, the layers are given by Roman 

 numbers, that is; I. means the lamina zonalis, II. means the 

 lamina granulans externa, which is not distinguishable in the 

 rat brain, III. means the lamina pyramidalis, IV. means the 

 lamina granulans interna, V. means the lamina gangUonaris and 

 VI. means the lamina multiformis. In several areas, some af 

 these Roman numbers are absent, implying that in these areas 

 the corresponding layers are not distinguishable or are lacking. 

 Mathematical symbols, as = or +, show the relations of the 

 thickness of each layer. Pyr. means pyramidal cells. If the cell 

 form is not specially given, it is assumed to be polymorphous. 

 The general characteristics of the lamination of the area are in- 

 dicated in brackets and some characteristics of the individual 

 layers are indicated by a word or two after the Roman number. 

 The absence of remark indicates the ordinary arrangement of a 

 layer. 



