348 
A MEMOIR UrON THE GENUS 
the eympbyeis is the same in tl.is speeies as i.. P. paludosus The dental foramina 
a e situated below the third pretnolar. The descriptmu of the jaw of r cnlMem 
has been largely taken from mandible No. 10,(127 m the Pnnceton collection, winch 
is associated with the facial portion of the skull already described ; and also fmm 
another specimen. No. 10,.381, better preserved than the former, which I consider 
as belonging to this species. 
TeLMATOTHERIUM HYOGNATIIUS. 
(Syn. P- hyognathus S. & 0.') 
The type of this species which was partially descrihecl hy Scott and Osborn, is 
a finely preserved jaw, No. 10,273 in the Princeton collection. There is also 
another portion of a mandible. No. 10,274 in the collection, which I think should 
be referred to this species. Both the jaws are from the W ashakie Eocene, and 
as yet I have not met with the species from the Bridger proper. 
Dentition, (PI. XI, figs. 10, 11).— I have referred jaw No. 10,273 to 
the genus Telniatotherium on account of the characters of the last molar, 
which agree in all essential points with those already described as 
belonging^ to T. mltridejis, namely, a high crown, with the posterior 
tubercle of the last inferior molar a well developed lobe. The incisors are 
of the Telmatotheroid pattern and are unusually procumbent, as they are 
nearly horizontally implanted in the jaw. They are of uniform size throughout, 
their crowns are very wide and low, excavated posteriorly, and show a well marked 
internal basal cingulum. There is no precanine diastema. The canines are very 
peculiar in form, and differ in this respect greatly from those of P. paludosns. They 
are implanted very obliquely, and as a consequence diverge much more Irom the 
jaw than in any other allied species. The crown of the canine, instead of being 
much elongated, round in section and strongly pointed as in P. paludosns, is short 
and rather broad, with a stout extremity. The external face of the canine 
is strongly convex, whereas the inner face is concave, the external lialf of 
the crown being bent away from the main axis of the tooth, thus leaving a broad 
inner basal portion which is much abraded in the type specimen. Tlie })eculiar 
form of the canines of this species is less well marked in jaw No. 10,274, whereas in 
jaw No. 10,273 the inner basal portion is not shai’ply marked off as in the other 
specimen. The diastema between the canine and ])remolarT is very long, being 
equal to twice the length of the diastema behind the first preniolar. The section of 
the first premolar shows it to have been a round tootli and its crown was probably 
much elongated. The second premolar is considerably worn, Imt enougli remains to 
show that its protoconid was very large and high. This tooth differs from that of T. 
adtridens in having a well developed anterior tubercle ; the liypoconid is large, Imt not 
nearly as higli as the protoconid. The remaining premolars jjosterior to the last 
are all badly damaged in jaw No. 10,273, whereas in the other example of this 
species premolars 3 and 4 are intact but much worn. The posterior V of the third 
minta Mammalia, page 513. 
