GEOWTH OF THE CEREBRAL CORTEX 549 



X', X'~YY', DD'-EE' and DD'~FF' in my sections. All of 

 these areas lie near to the cornu Ammonis and show a structure 

 somewhat different from that described by Fortuyn. But, for- 

 tunately, none of these areas include localities where measure- 

 ments of the cortex were made, so that the questions thus raised 

 may be reserved for discussion in another paper. 



In addition to the authors just cited, Brodmann ('09), in his 

 valuable work on the cortical localisation of function in ijiammals, 

 has examined the localisation in the cerebral cortex of the rabbit 

 (Lepus cuniculus) and of the spermophilus citellus, as the repre- 

 sentatives of the rodents. Though his description of the rabbit 

 cortex does not extend to the details of the structure of the cell 

 layers and for this reason, his 'Hirnkarte' can not be precisely 

 compared with my sections in respect to the laminar structure, 

 yet I think his diagrams do not deviate much from Fortuyn 's 

 map. For the sake of completeness, therefore, I give a table 

 collating his regional terms with the areas mapped by Fortuyn 

 and also with the corresponding areas shown in my own sections. 



Brodmanii's term, 

 (anatomico-physiological) Fortuyn My section^! 



Regio praecentralis f, f Areas AA'-BB', HH'-KK', KK'- 



LL', QQ'~RR'. 



Regio parietalis j, n Areas BB'-CC, LL'-MM', SS'- 



TT'. 



Regio occipitalis w Areas CC'-DD', UU'-VV. 



Regio insularis k Area MM'-OO'. 



Regio temporalis p, x Area TT'-UU'. 



Regio cingularis c Areas GG'-HH', PP'-QQ'. 



Regio retrosplenialis z, z", z'".. .No section. 



Regio hippocainpica r', s. 



Regio olfactoria h + h" Area 00' . 



VII. THE THICKNESS OF THE CEREBRAL CORTEX ACCORDING TO 

 BRAIN WEIGHT— TABLES AND CHARTS 



A. Direct measurements on the slide 



In the first instance, the thickness of the cortex was measured 

 at localities I-XIII inclusive, on the sections as prepared and 

 recorded without any corrections. 



