9Q9 



Cope] /wi/^ [Mareli 



M. M. 



Widtli crown at base, 0.0163 



" between apices lateral tubercles, .007 



Length, including median tubercles, .014 



" anterior median tubercle, .003 



Width '' i' u _008 



This is one of the interesting discoveries made by Dr. Lockwood, of 

 Keyport, N. J., in the fossiliferous strata of his region. He obtained it 

 of a farmer, with a number of other fossils of the upper marl bed in Mon- 

 mouth Co., ]Sr. J. The farmer used the marl of that stratum as manure, 

 and probably found the present specimen while digging it. The color of 

 the tooth is black like that of other Miocene and Eocene fossils of that 

 region, and though on application to a flame it shows the existence of a 

 small amount of carbonaceous organic matter, it does not give out the 

 odor perceived in the post-tertiary bones of New Jersey, when burned. 



Recently, my friend, Oliver IST. Bryan, sent me from Stafford Co., Vir- 

 ginia, a similar posterior molar from the inferior series of a hog. On con- 

 tact with a flame it evolves such an odor of organic matter, and combus- 

 tion leaves such distinct traces of carbon, that I am unwilling to consider 

 it a fossil. It is stained of a strong red color, which does not penetrate 

 far below the surface as does the black in the specimen above described. 

 Its posterior median tubercle is accompanied by a smaller tubercle on the 

 inner side; behind it an opposed pair of rudimental proportions follows, 

 and as the crown narrows to a sub-acute termination, a still lower median 

 tubercle finishes the series. The anterior extremity of the tooth is 

 broken away. In these unused crowns, the edges of the tubercles are 

 crenate, and the inner and median lobes and tubercles are coarsely plicate. 

 THINOTHERIUM, Cope. 



Family Hippopotamidce. Dentine thrown into transverse ridges on the 

 basal half of the second inferior incisor, otherwise probably as in Hexa- 

 protodon, or with three superior incisors at least. 



This genus is indicated by a second inferior incisor of the right side. 

 It resembles that of the genus Hippopotamus, but differs in the annulate 

 character of the surface of the dentine of the proximal portion of the 

 fang. The worn exterior face near the extremity, indicates the friction 

 of the usual large second superior incisor, while a correspanding worn 

 surface on the opposite side of the extremity, indicates the presence of 

 the inner or third superior incisor characteristic of Hexaprotodon and not 

 found in Hippopotamus. The base of the fang exhibit the usual short pulp 

 cavity, and is compressed, not rounded, as in Hippopotamus and Chcerop- 

 sis, as though there were an additional, or third inferior incisor also. 

 Apex of tooth narrowed obtuse. 



Structure of dentine concentric. 



TniNOTHERiTJM ANNUL attjm:, Cope. 

 Species nova. 



Second inferior incisor slightly curved both outwards and upwards. 

 Section of basal half, a vertical oval; beyond the middle, at worn surfaces, 



