90 BRITISH AND EUROPEAN FOSSIL ELEPHANTS. 



abroad, and, excluding the two ' talons,' the ridge-formula in 

 the African Elephant has appeared to me to be thus : — 



Milk molars. True molars. 



3 + 6 + 7 7 + 8+10 



3 + 6 + 7 7 + (8-9) + ll. 



The amount of development in the posterior talon is subject 

 to considerable variation. In some cases it forms merely an ■ 

 insignificant splent appended to the last ridge ; in others it 

 attains the proportions of a reduced ridge, and, according to 

 the degree of its evolution, it may be differently regarded by 

 different naturalists, either as a distinct ridge or as an ap- 

 pendage. The hypisomerous character of the ridge-formula, 

 in the intermediate molars of theLoxodons, is exhibited by the 

 succession of ciphers assigned above to the ridges in the last 

 milk molar and the antepenultimate and penultimate true 

 molars, i.e. 7 + 7 + 8. I have seen specimens in which the 

 penultimate true molar of both the upper and lower jaws 

 presented nine ridges. Cuvier states that he had never 

 observed a tooth of the African Elephant showing more than 

 ten plates. A last molar of the upper jaw, left side, procured 

 from Cape Coast by Mr. Samuel Turner, exhibits, in a 

 length of 11 inches, thirteen plates, i.e. eleven principal 

 ridges, besides front and back talons. 



The well-known and very constant distinctive characters 

 in the molars of the African Elephant consist of the rhomb- 

 shaped pattern yielded by the disc of the ridges after ad- 

 vanced wear, together with the relative narrowness of the 

 crowns as compared with those of the Indian Elephant. 

 (See PL VI. fig. 1, and vol. i. PL IV. fig. 3.) The sys- 

 tematic signification of these peculiarities appears to me to 

 be, that this species among the Loxodons represents the 

 group of forms in Trilaphodon and Tetralophodon, described 

 in the preceding part as having the ridges of their molars 

 characterized by outlying flanking tubercles and blocked-up 

 valleys, and as belonging to the ' Stenocoronine ' type. In 

 the African Elephant, the digital processes are less divided 

 and more speedily confluent than in .the Mastodons ; each 

 ridge throws out, in front and behind, a mesial angular pro- 

 jection, which meets or overlaps the corresponding part of 

 the next contiguous ridge ; and the transverse continuity of 

 the valleys, which are filled up with cement, is interrupted 

 in consequence. The adjoining rhombs, in the process of 

 wear, are in contact by their opposed angles, and at length 

 become confluent in a common disc. The angular expansions 

 of the discs are the modified homologues of the flanking 

 tubercles of the Mastodons ; and as the character prevails in 

 several forms among the latter, its presence in so pro- 



