HUMAN BRAIN-WEIGHTS. 357 



25*21 grammes less than the Roumani. The South Slavonian brains 

 are somewhat heavier than the Italian, but lighter than any of the 

 other peoples. One third of the Austrian Empire is peopled by Ger- 

 mans, descended from the natives of Austria proper. The Magyars 

 are Asiatics of the Mongolian race. The South Slavonians occupy the 

 most southern part of the empire, along the low-lying lands of the 

 Danube, which accounts for the small size of their brains ; while the 

 Italians are descended from the inhabitants of a still warmer region ; 

 all which goes to confirm the theory we have already announced, 

 that the smallest brains belong to the warmest climates. " On com- 

 paring the peoples of the four families represented here," continues 

 Dr. Wiesbach, " we find that the Slavonic family possess the largest 

 encephalon, the Romanic the smallest ; and that the intermediate 

 Magyars possess a more weighty encephalon than the Germans, which 

 are nearly equal to the Romanic stock." 



In a recently-published work Professor Bischoff, an eminent anato- 

 mist at Munich, gives the average brain-weight of males as forty-eight 

 ounces ("Nature," January 20, 1881) after weighing five hundred and 

 fifty-nine subjects, the obvious reason for the discrepancy between 

 him and the authors above mentioned being the fact that Munich, 

 situated in the southern part of Germany, is warmer than either Edin- 

 burgh or New York. 



Dr. Tiedemann, of Heidelberg, on the Alpine plateau of the Rhine 

 in Germany, where it is far colder than Edinburgh in winter, gave the 

 average male brain-weight, for the whole of life above puberty, as 53-25 

 ounces. Sir W. Hamilton, of Edinburgh, estimated the average adult 

 brain, without distinction of health or disease, at 48*25 ounces, for the 

 whole of life. In London, Dr. Sims found it 46*25 ounces. Luschka 

 gives 50*2 ounces as the average weight of a man's brain ; Krause 

 makes it 55*4 ounces, according to an article in the "Morning 

 Herald," Sydney, Australia. 



The above averages differ, from several causes. Dr. Tiedemann's 

 observations were limited to fifty-two subjects, and included both sexes, 

 but excluded negroes and very aged persons. Sir W. Hamilton had 

 sixty or seventy of both sexes ; Dr. Sims, two hundred and twenty ; 

 and Dr. Clendinning still more than Dr. Sims, whose patients were 

 largely among the aged, and those afflicted with long-standing disease. 

 Dr. Clendinning, in the Croonian Lectures, gives the following brain- 

 weights from male subjects, which show that the male encephalon 

 loses more than an ounce every ten years after it is fully grown : 



15 to 30 years 50 - 75 oz. 



30 to 50 " 49-66 oz. 



50 to 70 " 47-1 oz. 



70 to 100" 415 oz. 



Several other eminent anatomists have made similar exhibits 

 brain-weight decreasing as the intellectual power increases. It is 



