^ ON THE STRUCTURE AND CLASSIFICATION 
21o 
r • 1 fiibpirles of the median row are crescentic, and those of the 
l' The premote show four notches on one-half of the 
lateral rows are semi-crescen . J^^^onaing portion of the outer face; the 
»- i. . h. m.. 
latter surmou ^ representing the 
cingulum. 
The median crescentic and lateral semi-cre- 
scentic tubercles of this genus suggest the molar 
pattern of Stereognathus, in which the tubercles 
Fiat'RE 9. Maiiscfjisgus. — u. Probably an similarly shaped and disposed, but less 
upi>er molar viewed upon the wearing sur- , vniep n rlnnbl 
fai, enlarged two diameters ; b, probably numerous (Text. fig. 6, 5 ) and raise a doubt 
the inner face of an upper premolar; c, ^y^ether the type molar really belongs to the max- 
outer face of the same ; rf, anterior face of , . rpv 1 u 
the same. Cope Collection. Original. illary or mandibular series. The premolar, how- 
ever, resembles that of tlie maxilla of P. potens. Marsh, more closely than any of the 
known lower premolars. There is thus little doubt that Professor Cope has correctly 
placed this genus among the Plagiauladdce. 
2. BOLODONTID/E, Osborn h 1887. 
This family embraces Bolodon^ the closely allied genus Allodon and possibly 
Chirox. 
BOLODON. Owen, 1871. 
iPndlion, iM c" pm® m^. The second upper incisor is large, caniniform, 
sepamtc from its opposite fellow. The median incisor small or wantitig. The second 
incisor small, with a bicuspid crown, followed by a diastema. Premolars single 
fanged with faintly grooved sides and tricuspid crowns. The tubercles upon the 
molars conical, varying from two to four in each row. 
ALLOOON, Marsh , 2 1881. 
Dentition, i? c? pmf m^. This genus is separated from the foregoing merely 
by the presence of the small median incisor which has not as yet been observed in 
lim-RKlO. \iew8 of the maxilla of Allodon laticepa, Marsh; a, seen from below x 4. Allodon fortish, 
rremaxilla from the outer side, x3. c. The same from the inner side, s. Suture; o, Alveolus of lateral 
incisor or canine. A Uer Marsh. 
liolodon. 1 he diastema is narrower and it is possible that a weak canine is present. In 
all other respects, oven to the number of tubercles upon the molars, the genera are alike. 
I’roc. bhila. Acad., June, 1887. 
Am. Journ. Sc. and Arts, 1881, p. 511. 
