25 
the internal cusp is well developed. The heel is shorter than the 
blades of the crown, and is wide and without tubercles in its some- 
what worn condition. Its external border rises to an edge. The 
tubercular is wider than the corresponding tooth in the cotempo- 
rary species of Canidz, although not so wide as long. Its crown 
rises in two low tubercles which stand transversely near the middle. 
Measurements. M. 
Length of skull t6 orbit (axial). 3 é . 049 
Depth of skull to orbit (axial) . . .  . .042 
Interobital width .  °. % 5 : : . .040 
Width of nares ‘ : - . F . LT 
Length of superior molar series. 4 ; . 038 
Length of bases of three premolars : : - 019 
Length of base of sectorial . . é . - 018 
Width of sectorial in front. 7 : - . 009 
Width of first tubercular anteroposterior . . 006 
Width of first tubercular transverse ‘ z . O14 
Length of mandible to angle . % : : . 093 
Elevation at coronoid . F : : -  « 051 
Elevation at sectorial . ‘ ‘ : : . .020 
Length of inferior molar series. : , . 045 
Length of inferior sectorial . ‘ ‘ 3 . .014 
Length of heel of inferior sectorial : 5 . 003 
Length of inferior tubercular . . ‘ : . 006 
Width of inferior tubercular . 3 : é . 005 
Van der Hoeven has given' descriptions and figures of the 
skull and dentition of the Icticyon venaticus of Lund, of Brazil. 
From these it appears that the present species differs from the 
latter in the greater development of the inner part of the tuber- 
cular molar of the superior series; in LI. venaticus this part is 
much reduced. The tubercular molar of the lower jaw is also 
much smaller in the living species, the angular and coronoid pro- 
cesses less developed, and the condyle less extended transversely. 
The cranium of the £. crassivulitus is much more robust, but not 
much longer than that of I. venaticus. 
Discovered by J. L. Wortman in the Truckee beds of the White 
River, Tertiary of the John Day River region of Oregon. 
j 
1 Over het Geslacht Icticyon; wis. en natuurk. Verh. der Koninkl, 
Akademie, Amsterdam, Deel. III. 
