286 LLOYD’S NATURAL HISTORY. 
the structure of the base of if skull by which these primitive 
Cats differ from their modern allies, one of these being the 
presence of an alisphenoid canal. There is also a difference 
in the structure of the astragalus bone of the ankle, while many 
of these extinct Cats have a third trochanter to the femur, or 
thigh-bone. 
On account of these structural distinctions, these primitive 
Cats have been referred to a distinct Family, the Mimravide ; 
but in the structure of the lower carnassial tooth, as well as in 
some other features, they are clearly connected by means of 
Eusmilus and Macherodus palmidens with the more typical 
representatives of the latter genus, and it is thus evident that 
the whole assemblage forms but a single family group. 
The genus -4Zurictis, as represented by &. intermedia and 
two other species from the Upper Eocene of France and Wirt- 
temberg, has large upper canines, a small two-rooted anterior 
upper pre-molar, a small rounded upper molar inserted by two 
roots, a very small and single-rooted anterior lower pre-molar, 
and the lower molar (which may be wanting) also small and 
implanted in the jaw by a single root. Only fragments of the 
skull, which in the case of the type species indicate an animal 
nearly as large as a Leopard, are known. 
Vi. GENUS DINICTIS: 
Dinictis, Leidy, Proc. Acad. Philad. 1854, p. 127 ; Scott, Proc. 
Amer. Phil. Soc. 1889, p. 211. 
Dapiophilus, Cope, Rep. U.S. Geol. Survey for 1873, p. 508 
(1874). 
In this genus the skull is characterised by its short, vaulted, 
and generally Cat-like form, the first upper pre-molar being 
very minute and single-rooted, and the last molar transversely 
elongated, and inserted by three roots. In the lower jaw the 
first pre-molar is minute ; and the carnassial differs from that 
of .4/uric¢tts in having a cusp on the inner side of the blade, 
