320 PKOCEEDINGS OF THE &EOLOGICAL SOCIETY. 



inches. 



Length of crown 6*4 



Width of ditto 2-5 



Height at eighth ridge 5-5 



Another illustration of the saine kind is furnished by the polished 

 section of an entire upper antepenultimate, no. 2871 of the same 

 collection. 



The specimen presents fourteen principal ridges, without a poste- 

 rior talon. The dimensions are — 



inclies. 



Length of crown 6*8 



Height of ditto at the fifth ridge 4-8 



In this case if the two anterior ridges were worn somewhat lower 

 down, they would present but a single disk, with an appearance of 

 thirteen ridges to the crown. Although the last-mentioned speci- 

 mens show that the number of ridges in the antepenultimate some- 

 times ranges as high as fourteen, the other instances indicate that 

 the prevailing cipher is 12, or a repetition of that of the third milk- 

 molar. 



The j)enultimate or second true molar is described by De Blain- 

 ville as being composed, in the upper jaw, of seventeen ridges, and of 

 eighteen in the lower. Owen attributes, in general terms, to the 

 penultimate from seventeen to twenty ridges. Corse and Cuvier 

 have not specially defined it. A vertical section of an upper ante- 

 penultimate is represented in the 'Fauna Antiqua Sivalensis,' 

 plate 1. fig. 2, composed of seventeen ridges, with a reduced talon- 

 splent behind, the anterior talon being confluent with the first 

 ridge. The dimensions are — length of crown 8-5 inches, height of 

 crown at eighth ridge 6-2 inches. The anterior eight ridges are 

 worn. In the skull of a Malay Elephant in the Museum of the 

 Eoyal Asiatic Society the antepenultimate and the penultimate are 

 presented in situ, the former well worn, the latter in germ. The 

 penultimate in this case is composed of sixteen principal ridges, 

 with front and back talons. The typical specimen, figured and 

 described by De BlainviUe*, has a crown consisting of sixteen 

 principal ridges, with talons. The skull, no. 2659 of the Osteol. 

 Catal. Mus. CoUege of Surgeons, presents the xipper penultimate 

 on either side perfect, although partly worn, and the empty alveoli 

 of the germs of the last true molar behind. The crown of the 

 penultimate is composed of sixteen principal ridges, with a front 

 and back talon, of which the eleven anterior ridges are worn. 

 The dimensions are — 



inches. 



Length of crown . , 7-5 



Width of ditto in front 3-0 



Of the penultimate lower true molar, the majority of specimens 

 that I have examined have also presented sixteen principal ridges, 

 with talons, A fine illustration is afii'orded by the left ramus of the 

 '"■ ' Osteographie,' " Des Elephants," tab. 7. fig. 5 c. 



