THE TEETH OF PROBOSCIDEA. 351 



A pair of African tusks exhibited at the Great Exhibition 

 of 1851 weighed 325 Ibs., and measured eight feet six inches 

 in length, and 22 inches in circumference, but the average 

 tusks imported from Africa do not exceed from 20 Ibs. to 

 50 Ibs. weight. Indian elephants seldom have tusks attain- 

 ing very large dimensions ; one was, however, shot by Sir 

 Victor Brooke with a tusk 8 feet long, weighing 90 Ibs. 



The surfaces of the tusks of the female are often deeply 

 excavated about the level of the edge of the gum, and are 

 sometimes so weakened from this cause that they break off. 

 My friend Mr. Moseley tells me that he was informed by the 

 late Major Rossall, who as a sportsman had great knowledge 

 of Indian elephants, that the tusks of all the females he has 

 ever seen are so affected, and that the larvae or pupee of a 

 dipterous insect are often found bedded in the gum, and 

 attached to the surface of the tusk. There is a specimen of 

 a female elephant's tusk with the pupse attached in the 

 Museum of the Royal College of Surgeons. It would be a 

 matter of interest to ascertain whether the larva really eats 

 away the tusk, or whether the wasting of the tusk be due 

 to absorption set up by the irritated gum. 



The tusks of the elephant are implanted in long and 

 stout sockets, and grow from persistent pulps throughout 

 the lifetime of the animal. 



In the Indian elephant about one half of the length of the 

 tusk is implanted, and in young animals the pulp cavity 

 extends beyond the implanted portion, but in older animals 

 it does not extend nearly so far. A knowledge of its extent 

 is necessary, seeing that the tusks of captive elephants have 

 to be shortened from time to time ; this operation is by 

 some done frequently, by others only at long intervals, such 

 as ten years, in which case a large and valuable segment of 

 ivory is cut off, and the end of the tusk bound with metal 

 to prevent it from splitting. 



Tusks sometimes exemplify on a large scale the results of 



