OCR Text |
Show 125 Measurements. M. Length of inferior dental series 103 Depth of ramus at last molar 040 Depth of ramus at second premolar 0.30 Diameter of canine tooth 019 Length of premolar series - .035 Length of base of penultimate molar -... - 016 Length of base of last molar 019 Width of base of last molar 012 Elevation of crown of last molar -• 019 Length of superior last molar 020 Width of superior last molar 013 This animal differs in specific characters from the Wyoming carnivores, already referred to, iu the greater robastness of all its parts. From Synoplotherimn lanhiSj it also differs in the regular increase backward in the size of the molars. In the Wyoming species the penultimate is largest in the lower jaw. The fragments of the Oxyama forcipata are as large as corresponding parts of the jaguar. PACHY^ ENA ossrFRAGA, gen. et sp. nov. . Char. gen.- Established on a single superior'molar tooth of a large carnivore, apparently allied to the group of iiat- clawed Caitiivora. It is either the last premolar or first true molar. It is characterized by the absence of the cutting edge seen in the allied genera, and its replacement by a conic tubercle. The principal lobe is also a cone, and the inner one a perfect cone, a little less elevated than the principal one. Char, specif.- Crown with well- developed anterior and posterior basal tubercles; no ciuguii, either internal or external. Enamel slightly rugose. Measurements. M. Length of crown 020 Width of crowu 018 Elevation of anterior basal tubercle 006 Elevation of central cone :... .011 Elevation of Ulterior Cone 010 This is the largest carnivore yet observed in this formation, and of peculiar character; its structure indicating a diet not purely carnivorous. PROTOTOMUS vrvERRiNUS, gen. et sp. nov. Char. gen.- Three true molars in the maxillary bone ; premolars compressed, the last of the upper series triangular in form ; each angle enlarged ; the center of the crowu with a compressed conic tubercle. First and second true molars triangular, with a tnbercle at each angle, and two adjacent cones in the center. The tubercle of the posterior angle forms a slight, sectional edge with the posterior of the central pair. Last ( third moiar) transverse, with a median cone. Supposed mandible with the posterior two molars tubercular; the anterior tubercles similar to the posterior. This genus is evidently allied to the Virerridai, differing from Fi* rcrr « , so far as known, in the simple character of the last two inferior molars. From Limnocyon it differs, according to Prufcssor Marsh's descriptions, ill" possessing three instead of two superior true uiolars, or, if we include with these the last premolar, as does Professor Marsh, four instead of three. According to Professor Marsh, the tubercular molars in his Vulparus are generally similar to those of the existing genus Cams. Prototomus presents the number of superior molars seen in Amphicyon. Char, specif.- The P. vivei- rinus is established on a considerable part of the cranium and ektletou of one individual in good preservation. The last upper premolar is tri-radiare, having concave and subequal sides. The first molar is as broad as long, and is triangular, presenting a right angle outward and forward. The second molar is broader than long, and presents an acute tubercle on the anterior border between the inner and anterior median cones. There is a tubercle at the inner and onter extremities of the base of the last molar. No ciugulum on the posterior or onter sides of the last premolar. External cones of the last two itifcrior molars subcrescentic in section ; anterior inner obsolete ; posterior inner prominent. |