LECTURE IV. ' 111 



whose intelligence nothing is said, 85 ; for the brain of a com- 

 mon day-labourer named Krebs, 73 ; and for the brain of an 

 idiot who died, aged twenty-six, only 15, a diminution which, 

 as you will observe, tallies with the hypothesis, that great de- 

 velopment of the frontal convolutions, and consequently of the 

 convolutions generally, is connected with the development of 

 intelligence. 



We may here observe that Wagner has also in the case of 

 twelve brains endeavoured to ascertain the proportion between 

 the measured convex surface, the extent of which also depends 

 upon the development of the sulci, and the cerebral weight. 

 As a general result it appears that the heavier the brain, the 

 greater is the development of the surface ; but that in the 

 female sex the lesser weight, already alluded to, is compensated 

 by a larger development of surface. Omitting from the twelve 

 the three female brains, and having regard only to the eight 

 male brains (the twelfth belonged to an idiot) we find a similar 

 compensation in the male brain which, according to weight oc- 

 cupies the fifth, but according to surface the third place. This 

 condition is, however, more strikingly exhibited in females, 

 since the heaviest female brain in the whole list occupies but 

 the eighth place, whilst, with regard to surface, it occupies the 

 second place. In the same way the female occupying the tenth 

 place would advance to the ninth, and the one occupying the 

 eleventh would advance to the eighth. Subjoined is Wagner's 

 table, in which the brains are arranged in a double series ac- 

 cording to weight and according to surface, so as to present 

 their relative proportions as clearly as possible : — 



No. 



Wc 



iight in Grammes. 



Convex surface in squares 

 of 16 square millimeters. 



1. (Dirichlet) - 



2. (Fuchs) 



3. (Gauss) 



- 



1520 

 1499 



1492 



- 



- 



2553 



2489 

 2419 



4. (Herniann) 



- 



1358 



- 



- 



2406 



5. Male - 



- 



1340 



- 



- 



2451 



6. Male - 



- 



1330 



- 



- 



2309 



7. Male - 



- 



1273 



- 



- 



2117 



8. Female 



- 



1254 



- 



- 



2498 



9. (Hausmann) 



- 



1226 



- 



- 



2065 



10. Female 



- 



1223 



- 



- 



2272 



11. Female 



- 



1185 



- 



- 



2300 



12. Microcephalo 



- 



300 



- 



- 



896 



