FUNCTIONS OF THE CEREBELLUM. 203 



The average proportion of the weight of the Cerebellum to that of the Cere- 

 brum was 1 to 6-59 ; the highest being 1 to 5*09, and the lowest 1 to 7. The 

 proportion was, therefore, considerably higher in the perfect female than in 

 the perfect male. In the twenty-one Geldings, the average weight of the 

 Cerebrum was 419 gr. ; the highest being 566 gr., and the lowest 346 gr. 

 The average of the Cerebellum was 70 gr. ; the highest being 76 gr., and 

 the lowest 64 gr. The average proportion was, therefore, 1 to 5-97 ; the 

 highest being 1 to 5-16, and the lowest 1 to 7'44. It is curious that this last 

 was in the individual which had the largest Cerebellum of the whole ; but 

 the proportional weight of the Cerebrum was still greater. 



277. Bringing together the results of these observations, they are found to 

 be quite opposed to the statement of Gall. The weight of the Cerebrum, 

 reckoning the Cerebellum as 1, is thus expressed in each of the foregoing 

 descriptions of animals. 



Average. Highest. Lowest. 



Stallions . . . 7-07 7-46 6.25 



Mares . . . 6-59 7-00 5-09 



Geldings . . 5-97 7-44 5-16 



The average proportional size of the Cerebellum in Geldings, therefore, is so 

 far from being less than that which it bears in entire Horses and Mares, that 

 it is positively greater ; and this depends not only on diminution in the rela- 

 tive size of the Cerebrum, but on its own larger dimensions, as the following 

 comparison of absolute weights will show : 



Average. Highest. Lowest. 



Stallions ... 61 65 56 



Mares ... 61 66 58 



Geldings ... 70 76 64 



The difference is so remarkable, and appears, from examination of the indi- 

 vidual results, to be so constant, that it cannot be attributed to any accidental 

 circumstance, arising out of the small number of animals experimented on. 

 The average weight of the Cerebellum in the ten Stallions and twelve Mares 

 is seen to be the same ; and the extremes differ but little in the two ; whilst 

 the average in the Gelding is more than one-seventh higher, and the lowest is 

 considerably above the average of the precedingpvhile the highest far exceeds 

 the highest amongst the entire Horses. It is curious that Gall would have 

 been much nearer the truth, if he had said that the dimensions of the cere- 

 brum are usually reduced by castration ; for it appears from the following 

 table that this is really the case : 



Average. Greatest. Least. 



Stallions ... 433 485 350 



Mares ... 402 432 336 



Geldings . . .419 566 346 



The weight of the largest Cerebrum of the Gelding is far above the highest 

 of the Stallions ; but it seems to be an extraordinary case, as in no other was 

 the weight above 490 gr. If this one be excluded, the average will be 

 reduced still further, being then about 412 ; this may be seen by looking ovrr 

 the whole table, to give a very fair idea of the'usual weight in these animals, 

 which is therefore less, by about one-twentieth, than the average of the Stal- 

 lions. The increased size of the Cerebellum in Geldings may perhaps be 

 accounted for, by remembering that this last class of horses is solely employed 

 for its muscular power, and that the constant exercise of the organ is not 

 unlikely to develop its size ; whilst Stallions, being kept especially for the 



