44 BRITISH AND EUROPEAN FOSSIL MASTODONS. 



fragment, being referable to an inferior incisor of the Simorre 

 M. (Triloph.) angustidens of Cuvier; and it would seem to me 

 that they are equally irreconcileable with its being considered 

 as a lower tusk of M. (Tetralophodon) longirostris, for the sym- 

 physial beak required for the implantation of a tusk of such 

 magnitude would be enormous, and is unknown among any 

 of the species of Mastodon. Professor Owen describes the 

 specimen as being traversed from end to end by a sub-central 

 canal. The same character has been observed in the upper 

 tusks of other fossil Proboscidea, and is nowise characteristic 

 of a lower incisor. I consider that the specimen in question 

 is not a fragment of a lower, but of an upper tusk near the 

 point ; and it differs in no important respect from the un- 

 doubted upper tusks of M. (Tetralophodon) Arvemensis seen 

 in the Museums of Florence and Turin, which are either 

 slightly curved or twisted in a gentle spiral direction, as 

 represented in the figure given by Sismonda 1 of the Dusino 

 skeleton. 



In corroboration of this view, it may be stated that the 

 Indian fossil species which we have named If. (Tetralophodon) 

 Sivalensis is in some respects more nearly allied to the Crag 

 species than the latter is to either M. (Trilophodon) angusti- 

 dens or M. (Tetralophodon) longirostris. It shows the same 

 alternate character of the marainillse of the ridges of the 

 ' intermediate molars,' and it appears to have been equally 

 destitute of inferior incisors. I have examined a large 

 number of lower jaws of this species, of all ages, from the 

 sucking calf up to the adult animal, specially with a view to 

 the detection of these teeth, and never observed the slightest 

 indication of their presence in any specimen, whether in the 

 Indian fossil collection of the British Museum, at the India 

 House, or in the rich series belonging to the Asiatic Society 

 of Calcutta. 



This completes what I have to bring forward in the shape 

 of descriptive and comparative details, in order to indicate 

 the most prominent diagnostic characters derivable from the 

 teeth and jaws of the Crag Mastodon. I believe that the 

 differences of the three species included by Cuvier under the 

 name of Mastodon angustidens will be found to be carried out 

 through all the principal bones of the skeleton. It would 

 be wholly out of place to enter upon such osteographical par- 

 ticulars on the present occasion ; but a good idea of the 

 general character of the skeleton in each may be attained by a 

 reference to two well-known standards of comparison, namely, 

 the existing Indian Elephant and the Mastodon of North 



1 Op. cit. tab. i. figs, -i and 5. 



