DENTITION". 223 



respect to the corresponding teeth of the existing Indian 

 Elephant. Some of the plates show a considerable amount 

 of undulation in the general sweep of the machcerides, but 

 there is no tendency to the mesial expansion, or outlying 

 loop, seen in E. antiquus. The five posterior ridges are all 

 more or less affected by wear ; the most of them present 

 distinct annular discs on the tips of the digitations, which 

 are seen to be of large size, as in E. planifrons and E. 

 meridionalis. The eighth ridge shows these annular discs 

 semi-confluent into a transverse depression. The ninth 

 presents five worn digitations ; the tenth and eleventh, 

 six; and the twelfth, five. There is no mark of pressure 

 behind, proving the tooth to be the last of the molar 

 series. The space occupied jointly by the first six dis- 

 tinct transverse discs amounts to 5 - 4 inches, giving an 

 average of nine-tenths of an inch to each ridge. This is 

 considerably greater than that shown by the crown of the 

 Georgian molar, but it is to be borne in mind that the 

 difference is accounted for by the teeth being hi different 

 stages of wear. 



The principal dimensions are : — 



Extreme length of crown, 12-5 in. Width of ditto, at first transverse disc, 3-0 

 in. Ditto, at fifth ditto, 3-7 in. Ditto, at eighth ditto, 3'8in. Ditto, at ninth 

 ditto, 3-1 in. Height of crown at ninth ditto where high'est, 5'4 in. Space in 

 length occupied by the six anterior distinct discs of wear, 5-4 in. 



Making allowance for the part of the tooth borne upon 

 the anterior fangs, which has been worn away, the entire 

 molar must have been of very large size ; and it indicates a 

 species that attained colossal dimensions. 



Other illustrations of E. Columbi are furnished by a col- 

 lection of fossil bones, part of which was purchased for the 

 British Museum in 1847. They are stated to have been 

 found by Mr. W. Huff on the banks of the Brazos Eiver, near 

 San Felipe de Austin in Texas. One of the specimens, a 

 fine Bovine skull (Bison latifrons, Leidy), is identifiable with 

 a figure given by Dr. W. M. Carpenter, of New Orleans, who 

 published the first account of these remains. Among them 

 were numerous fragments of bones, said to have been of 

 Elephant and Mastodon ; the teeth of Elephants, especially, 

 predominating. A proboscidean tusk measured eleven feet 

 in length, and twenty-six inches in girth at the base ; but 

 no details are given regarding the molars of Elephas. 1 In 

 the series, belonging to the National Collection, reputed to 

 be of this origin (Nos. 20,701-5 MSS. Eegister) is a superb 

 specimen (No. 20,702) of a last molar of the lower jaw, right 

 side, comprising the posterior three-fourths of the crown in 



1 Silliman's Journal, 1846, 2nd ser., vol. i. p. 245. 



