168 



divided into two small and transversely situated mammillae. The depth of 

 the jaw anterior to this molar is not materially increased to form the 

 symphysis, and the upper margin extends forwards in front of the molar 

 in the same horizontal line with the plane of the socket, instead of sinking 

 down to join the symphysis, in which respect the present species of 

 Mastodon resembles the Mast, giganteus, and differs from the Mast, 

 elephantoides and from the Elephant. 



From the tertiary formations of the Sub-Himalayan district, India. 



Purchased. 



691. A plaster cast of a portion of the crown of the left lower molar of the 



Mastodon angustidens , Cuv. It corresponds precisely in size, form and 

 alternate disposition of the mammillary processes, with the preceding 

 specimen, and presents the smallest posterior ridge and the three pairs in 

 advance ; the anterior pair and part of the inner side of the tooth having 

 been broken off. 



From the older pliocene tertiary fluvio-marine Crag of Norfolk. 



Presented by Robert Fitch, Esq., F.G.S. 



692. A plaster cast of the crown of a left lower molar of the Mastodon 

 angustidens, Cuv. The posterior talon is relatively smaller than in No. 

 691, but the larger pairs of mammillary processes present the same 

 alternate arrangement as in the preceding specimens. 



From the miocene tertiary formations of Baltimore. 



Presented by Dr. Richard Harlan. 



693. A plaster cast of a portion of the right upper jaw of a very young 

 Mastodon angustidens, Cuv. (Mast, longirostris , Kaup), showing the two 

 deciduous molars which are shed and replaced vertically ; and the second 

 permanent molar, or that which succeeds the first of the series that 

 comes into place vertically : both these are subsequently shed by hori- 

 zontal displacement, like the molars of the Elephant, 



From the miocene tertiary formations at Epplesheim in Rhine Hessia. 



Presented by Dr. Kaup. 



694. A plaster cast of the palatal and alveolar portions of the maxillary bone 



