356 FUNCTIONS OF THE NERVOUS SYSTEM. 



from seven to sixteen years ; and in twenty-one Geldings, aged from seven 

 to seventeen years. The average weight of the Cerebellum in the Stallions 

 was 433 grammes; the greatest heing 485 gr., and the least (which was in a 

 horse of ten years old) being 350. The average weight of the Cerebellum 

 was 61 gr. ; the greatest being 65 gr., and the least 56 gr. The average pro- 

 portion borne by the weight of the Cerebellum to that of the Cerebrum, was, 

 therefore, 1 to 7'07 ; the highest (resulting from a very small Cerebrum) being 

 1 to 6'25 ; and the lowest (resulting from an unusually large Cerebrum) being 

 1 to 7'46. Throughout it might be observed, that the variation in the size of 

 the Cerebellum was much less than in that of the Cerebrum. In the twelve 

 Mares, the average weight of the Cerebrum was 402 gr. ; the highest being 

 432 gr., and the lowest 363 gr. That of the Cerebellum was 61 gr. ; the high- 

 est being 66 gr., (which was in the individual with the smallest Cerebrum), 

 and the lowest 58 gr. The average proportion of the weight of the Cerebel- 

 lum to that of the Cerebrum 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 curi- 

 ous, 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. 



469. 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 de- 

 scriptions of animals: 



Average. Highest. Lowest. 



Stallions .... 7-07 7-46 G"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 dimension, 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 preceding, while 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 



