556 NAOKI SUGITA 



r - T -V W'.-B (fresh) 



W ./> (on slide) ^ 



where AB is the greatest width of the brain (fig. 12). The 

 thickness of the cortex, at locaUties IX-XIII was corrected by 

 the use of this coefficient. 



Mil. CORRECTED DATA PRESENTED IX TABLES AND CHARTS 



Tables 6, 7 and 8 show the corrected values of the cortical 

 thickness at the thirteen locaHties in the three kinds of sections 

 examined. The data for the coefficients employed in correct- 

 ing the individual entries are given separately together with 

 the coefficients for each brain weight group. The method of 

 applying the coefficients has already been described. The 

 average thickness of the cortex for each brain was obtained 

 from the corrected individual measurements. Charts 3 to 8 

 are based on the foregoing tables, charts 3, 5 and 7 showing the 

 individual measurements and charts 4, 6 and 8 the average 

 \'alues of each locality for each brain weight group, in sagittal, 

 frontal and horizontal sections respectively. 



In tables 6, 7 and 8, the endeavor has been made to introduce 

 all the details necessary for the interpretation and control of the 

 results. In table 6, for example, the entry III a, age 2 days (see 

 also table 1), is for a rat having a brain weight of 0.3105 g.-ams. 

 For the correction of the observed cortical thiclvness in the sagit- 

 tal section, the coefficient was found by formula (1) page 554. 

 This correction coefficient was applied to the measurements, as 

 made on the slide, for each of the localities I to V at which the 

 thickness of the cortex in the sagittal section had been deter- 

 mined. For each locality the corrected measurement in milli- 

 meters is given in the table and at the end of the line the aver- 

 age of the five corrected values appears. 



Similarly by using the correction coefficient determined by 

 formula (2) correction has been made in a like manner for the 

 direct measurements at the three localities VI-VIII in the frontal 

 section, table 7, taken from the other hemisphere of the brain, 

 one hemisphere of which had been used for the sagittal section. 



