30 MR. A. L. ADAMS ON THE OSTEOLOGY OF 



The configuration of the latter varied, no doubt, individually, as obtains in all known 

 species, some crowns being longer and narrower and holding an additional ridge. The 

 worn disk, however, might have always been much the same ; and although the enamel 

 was thick as compared with the penultimate molar, it was in no way, as regards C Series, 

 remarkable, the ridge-formula of which seems to have varied from fourteen to fifteen 

 ridges or twelve plates and two talons, which were contained in from 6*5 to 8 inches. 



4. The two imperfect but highly suggestive members of D Series seem to stand to 

 those of C Series as the thick- and thin-plated molars of A and B Series, only that the 

 latter do not show the decided larger dimensions we find between D and C Series. Again, 

 just as the second true molar, PI. XI. fig. 10, was correlated with the last true molars 

 of C Series on the score of dimensions, so we find a proportional agreement between the 

 large molars of C Series and the large upper and lower penultimate molars, PI. III. 

 figs. 1 and 2. 



Now such discrepancies suggest the question as to whether we are to assume the 

 previous existence of two fonns of Elephant, a small and a large, each displaying cha- 

 racters in last true molars similar to what obtains in other species of Elephant, or to 

 consider the wide differences of the plates specific characters. If we adopt the latter, 

 then the forms indicated by the last true molars would be doubled, which, considering 

 the ridge-formula and crown-constituents, cannot be well admitted. Hypothetically I 

 am disposed, from a consideration of the molars and what obtains in other members of 

 the genus, and from what will appear when I come to consider other portions of the 

 skeleton, to believe that the C and D series and the largest penultimate true molars, 

 PI. III. figs. 1 and 2, belonged to full-grown individuals of the largest form, and that in 

 dimensions their teeth equalled and sometimes exceeded the ordinary dimensions of the 

 penultimate true molar of Elephas antiqxius, which usually held the same ridge-formula 

 in from about 8"5 to 9'5 inches. 



From the foregoing data the ridge-formulas of the molar series are deducible 

 apparently as follows \ — 



Large Form. 



III. Cranium. 



I have no evidence of the configuration of the dome of the cranium in any of the 



Maltese fossil Elephants. Besides abundant remains of fragments of the skull, including 



the petrous portions of the temporal bone which contained the internal ear, there is a 



condyle of the lower jaw (PI. VIII. fig. 6). It is of the right side, and evidently belonged 



' The two talons are included. 



