NOTES ON THE CANIDH OF THE WHITE RIVER OLIGOCENE. 307 
Poebrotherium. In Daphenus it is only the proximal portions of the two shafts which 
are thus closely pressed together ; for the greater part of their length they are not in 
contact, and thus preserve the primitive oyal section. As their divergence is due to the 
relative positions of the tarsal bones, there is no necessity for the lateral curyature of the 
distal ends. The two metatarsals are very closely interlocked and in much the same 
fashion as in Canis. On the head of mt. iv are two facets for mt. ili, of which the dorsal 
one is a stout hemispherical prominence, which is received into the pit on the head of 
mt. ii, already described. The plantar facet is actually upon the plantar rather than on 
the tibial face of the bone ; the prolongation from the head of mt. iii extends around and 
embraces this facet, and by means of the double articulation a very firm interlocking of 
the two bones is effected. On the fibular side of mt. iv is a large and deep depression 
which receives the projection from mt. y. The facet for the head of the latter is large, 
slightly concave, and continues without interruption from the dorsal to the plantar 
border, while in Canis there are two distinct and quite widely separated facets. The 
shaft resembles that of mt. iii, but is somewhat more slender. In both of these meta- 
tarsals the distal carina is placed symmetrically with reference to the trochlea, but is less 
compressed and prominent than in Canis. 
The fifth metatarsal is not completely preserved in any of the specimens, the only 
representative of it being the proximal end, belonging to a large individual of D. vetus 
(No. 11423). As the specimen is incomplete, nothing can be determined respecting its 
length, but probably this was equivalent to that of mt. ii, the two forming a symmetrical 
pair, much as in Dinictis, though mt. y, so far as it is preserved, seems to be somewhat 
the stouter of the two. On the fibular side of the head is a very prominent projection, 
ending in a roughened thickening, and directed obliquely outward and upward, the 
“ascending process ” (aufsteigender Fortsatz) of which Schlosser speaks in the passage 
already quoted. In the recent dogs this process is very much reduced, while in Dinictis 
it is of quite a different shape. In the Machairodont the process is a long and promi- 
nent ridge, extending along the whole dorso-plantar thickness of the head, and projects 
much more proximally than externally, while in Daphewnus it is a blunt hook which 
projects more outward than upward. ‘The Machairodont Hoplophoneus has the process 
developed in very much the same way as in Daphenus. 
The facet for the cuboid differs from that of Canis in being quite concave transversely 
and in presenting as much toward the tibial side as it does proximally, while in the 
modern genus the facet is small, plane, subcircular in outline and altogether proximal in 
position. On the tibial side is a rounded protuberance which fits into the pit on the head 
of mt. iv; this protuberance is more prominent than in Canis and decidedly more so than 
in Dinictis. What little of the shaft is preserved is transversely oval in section, with a 
