author's abstract of this paper issued 

 by the bibliographic service, june 21 



COMPARATIVE STUDIES ON THE GROWTH 

 OF THE CORPUS CALLOSUM 



I. ON THE AREA OF THE CORPUS CALLOSUM, MEASURED ON THE 

 SAGITTAL SECTION OF THE ALBINO RAT BRAIN 



NOBUHARU SUITSU 

 The Wislar Institute of Anatomy and Biology 



TWO FIGURES AND FOUR CHARTS 



Concerning the exact function of the corpus callosum there is 

 still much question. The importance of the callosum in man is, 

 however, clear from the fact that its absence or disease of it is 

 often attended by more or less profound weak-mindedness or 

 downright idiocy (Eichler, Knox, Urgart, Ward, Huppert, 

 Gausser: cited from Onufrowicz, '87; Kaufmann, '87; Hochhaus, 

 '93). 



Some cases of the partial absence of this structure do not 

 exhibit, however, any serious deviation from the normal, though 

 such individuals have been classed by their acquaintances as 

 'queer' (Nobihng-Bayer, Birch-Hirschfeld, Jolly: cited from 

 Onufrowicz, '87). 



Spitzka ('07) and Cameron ('17) have stated that the area of 

 this commissure in the sagittal section is unusually large in the 

 brains of individuals of recognized intellectual ability. 



Further, Spitzka ('07) stated that the size of the callosum 

 bears a relationship to the degree of intellectual superiority.. 

 Whether or not Spitzka is right in declaring that talented men 

 have larger callosa when compared with ordinary men, can be 

 answered only after a more complete study on the growth of 

 callosal area in man, when considered in relation to the recorded 

 brain weight and the abundance of the convolutions. 



As a first step toward further knowledge of this structure, I 

 have undertaken, at the suggestion of Professor Donaldson, to 



35 



