276 APPENDIX. 



It lias only 13 crown ridges, and is therefore little above a 

 medium -sized tooth."-^ The crown resembles a small Belgian 

 paving stone, while the taper of the root resembles that of a 

 heart. 



The elephant is a vegetarian, and the construction of its 

 grinders is a striking example of the adaptation of the teeth of 

 an animal to its food. 



Tiie tnsks, two in number and belonging to the upper jaw, 

 are shed but once. The deciduous tusks cut between the fifth 

 and seventh months and are shed about the end of the first 

 year, their roots being considerably absorbed. They rarely 

 exceed 3 inches in length and ^ of an inch in diameter. About 

 two months after the shedding of the temporary tusks, the 

 permanent, which are situated to the inner side of and behind 

 the former, emerge and continue to grow throughout life. They 

 have an enamel coat, but are mostly composed of ivory , a 

 remarkably fine and elastic form of dentine (differing somewhat 

 from the dentine of other teeth), and are hollow for a consider- 

 able part of their length. Thej are deeply imbedded in the 

 skull. Sir Samu2l Baker found one 8 feet long with 22 inches 

 girth to be imbedded 31 inches. 



The tusks, which are formidable defensive and offensive 

 weapons, and which correspond to the canine teeth of other 

 animals, vary much in length, weight, and curvature. Gordon 

 Gumming found a tusk in Africa that measured 10| feet and 

 weighed 173 pounds. The average, however, is not over 7 feet 

 and 103 pounds. They are generally smaller in the female 

 than in the male, but accordin2: to Cuvier the African species 

 are the same in this respect. In the Indian elephant some have 

 a pronounced upward curve, some are nearly straight, while 

 others resemble the letter S. They are sometimes used, as 

 levers in uprooting mimosa trees whose crown of foliage is 

 beyond the reach of the trunk. In Ceylon, where the elei)harit 

 lives chiefly on grass and herbage, the tusks are generally 

 absent in both sexes. The bullets sometimes found in the 

 ivory are probably first lodged in the pulp cavity and then 

 carried to the solid part by growth. 



* Mr. L. G. Yate« of CentCM-ville, California, says fossil elephant molars 

 weighing 25 pounds have been discovered in that State. 



