1852.] 



5 



a little larger than the adult D. torquatus ; the only measurements that can be 

 given are the following, in English inches : 



Distance between the frontal foramina 1'2. 



Third premolar : lateral diameter -45 : antero-posterior diameter '4. 



Fourth premolar: lateral diameter '46 : antero-posterior diameter '5. 



First molar: lateral diameter 55 ; antero-posterior diameter '63. 



Inferior canine : length 3'75 ; posterior breadth '48 ; radius of curvature 2*75. 



Humerus: diameter of inferior extremity 1-52; breadth of larger articular groove, 

 .75 ; smaller groove '4 ; least distance from lower margin of larger groove to fora- 

 men 67. 



Innominatum : diameter of acetabulum 1-2; least breadth of ilium 1"0. 



Femur: length 6*85 ; from fovea on head,toextremity of trochanter major 1*72; 

 breadth of tibial articular groove anteriorly '8 ; transverse diameter of condyles 

 posteriorly 1'55. 



Metatarsal: length 2*87; of inferior articular surfaces, lateral diameter 46; 

 antero-posterior diameter '57 ; length of first phalanx 1-25; second phalanx '95. 



Calcaneum : length 2*45: greatest breadth 1'12; from fibular to apical process "91. 



Condyle of lower jaw ; breadth 1*2 ; antero-posterior diameter of articular 

 surface 6. 



Protochcerus prismaticus Lee. Am. Journ. Sc. 2nd series 5.105. 



To the description of the teeth of this animal, I have only to add that the fang 

 of the canine is very similar to that of Sus babiroussa ; the posterior molar bears 

 considerable resemblance to that of Sus babiroussa, as represented by Blainville, 

 (plate VIII.) although the student will fail to find the resemblance in nature. The 

 Anthracotherium tooth figured in Owen's Odontography, with which I formerly 

 compared this tooth, differs in having the lobes connected by an elevated ridge. 



The dimensions of the teeth are as follows, and indicate an animal smaller than 

 a Peccary. 



Inferior canine : length of worn surface 1*35 ; breadth -3 ; radius of curvature of 

 posterior face and margin 2*46. 



First inferior molar : lateral diameter '39 ; antero-posterior diameter '52. 



Last inferior molar : breadth '5, from posterior lobe to middle lobe '26; to 

 summit of anterior lobe '58, 



Notice of a fossil Dicotyles from Missoiiri. 

 By John L. Le Conte, M. D. 



The Tooth which forms the subject of this communication, was found with 

 some mastodon bones in Benton County, Missouri, and was presented to me by 

 Dr. R. W. Gibbes. 



It is a right lower canine, wanting the fang, and attached to a small piece of 

 jaw, containing alveoli of three incisors. 



The tooth has precisely the same direction as in D. torquatus, but is somewhat 

 less compressed ; the anterior edge is very acute ; on the part of the fang which 

 remains, no vestige of external and internal grooves exists ; the posterior groove 

 is well marked as in D. torquatus; on the outer surface of the tooth, nearer the 

 posterior than the anterior margin is an elevated ridge, acute at summit, which 

 extends along the whole of the enamelled part of the tooth. This character is not 

 to be found in T). torquatus ; the very obsolete elevation which exists there being 

 a consequence of the continuation of the grooves impressed on the internal face of 

 the fang; I have also failed to discover a similar elevated line on the canine of any 

 species of Sus which has come under my observation. 



As this seems to be a character of sufficient importance to separate the species 

 co-existent with the Mastodon, from any now living, 1 would give to it the name 

 ofDicotylescostatus. 



Although there is no character in this canine to make a reference to Dicotyles 

 more certain than to Sus, yet as the latter genus has not been distinctly proved to 



