THREE EXTINCT SPECIES OF ELEPHANT. 301 



not more than two annuli, which are of lai'ge size and with thick enamel, whilst in fig. 9 

 the corresponding plates show five or six annuli, of small size, and a corresponding thin 

 enamel. The above differences appear to me to be quite as important as those which 

 exist between the true molars of the Indian and African species, and infinitely greater 

 than those which distinguish the former species from E. primigenms. 



In fig. 10 is shown the crown surface of a tooth from Maccagnone, which would seem 

 in its size and characters to approach veiy nearly to the type of fig. 9 ; and 1 presume 

 that Dr. Falconer may have introduced the figure with the view of showing some relation 

 between the Sicilian and Maltese teeth. He has, however, left no observations on this 

 point ; and as the tooth itself is not now with the others, I am unable to say more about 

 it than is shown in the figure. 



With regard to the milk-teeth, we have not the same facility of judging of their 

 relations from the thickness of the plates alone as we have in many cases in the true 

 molars. In this respect little or no difference will be observed among the various 

 milk-teeth of which figures have been given; and some might thence, under the 

 circumstances, be led to conclude that these teeth must all belong to one only of the two 

 species whose molars diff'er so widely in the thickness of the plates. But such a con^ 

 elusion is by no means warranted by what we know of the milk-teeth in different species 

 of Elephant, in which, notwithstanding very great differences in the thickness of the 

 plates in the true molars, little or none will be found in that of the plates of the 

 respective milk-teeth, whilst in some cases the difference in this regard will even be in 

 an opposite direction to that in which it might be expected to show itself. For instance, 

 the mean thickness of the true molar plates in E. africanus varies from 0"-85 to 1" or 

 more, and in E. indicus is about 0"-55, whilst the thickness of the plates ia the m.-m. -5 

 of the two is pretty nearly the same, or about 0"'3ii-'33 ; in E. primi genius, although 

 the thickness of the plates in m. 1 is not more in most cases than about 0"'48--45, those 

 of the ord m.-m. average about 0"'34, or rather more than in E. africanus, though con- 

 siderably less than in E. antiquus, in which the thickness may be taken at about 0"'41. 



As we cannot, therefore, rely solely upon the thickness of the plates in the milk-molars 

 as a diagnostic character in species so widely distiuguished as E. indicus and E. africanus, 

 it is impossible from that character to say whether or not all the milk-molars in the 

 Zebbug collection belong to one or more species. Had they all been so worn as to 

 afford a good view of the form of the machserides, the decision would probably have been 

 easy enough ; but it will be observed (leaving out of the question the m.-m. 'Z, fig. 2) that 

 only three of the specimens were worn sufficiently for this purpose ; and as, from the 

 form of the machaerides in these instances, and the general condition and colour &c. of 

 the teeth, it is not improbable that all belonged to one and the same individual, we must 

 have recourse to other characters to determine the question of the true relations of the 

 unworn specimens. I am not sure how far such a character may be depended upon; 

 but, in the case more especially of milk-teeth uncovered with cementum, I think what 



2 T 2 



