13LAKE — EYIDE>'CES OF HOESES IN THE NEW WOELD. 27 
species of Hipparion and Equus should exhibit the more generalized 
type of perissodactjle dentition. 
Eqcts piscenensis, Gervais, Zool. and Pcdeontol. Frangnises, 
p. G7, pi. 21, Jigs. 9, 10. .(Upper portion of the cannon bone of the 
forefoot ; first plialanx.) This species, smaller than the horse, has 
been founded by INI. Gervais on the above bones of the extremities. 
The teeth are wholly unknown. 
Geog. Distrih. liight bank of the -tiiege, near Pezenas (Herault). 
— Geol. Age. Pliocene. 
Equus pal^onus, Equus siYALENSis, Equus Namadicus. — Tliese 
three species are figured in Falconer and Cautley^s ' Fauna Antiqua 
Sivalensis' but no description is there given. The figured specimens 
are in the British Museum. 
Eqfus cuevtdens, Owen in 'Fossil Mammalia of the Voyage of the 
Beagle; p. lOS, pi. S2,figs. 18, 14. 
Characters. — Molar teeth left side upper jaw, slicrhtly smaller and more curved than 
E. caballus. A superior molar of the right side was derived from Bahia Blanca, but its 
friable condition precluded its representation in Professor Owen's work. 
Geog. Distrih. Punta Alta (Bahia Blanca), Santa Fe in Entre Rios. 
— Geol. Age. Pliocene. 
Equus neog-EUS, Lund. — Syn. Equus macrognathus (TVeddell, p. 
204). E. principalis, Lund, Ann. des Sci. Nat. xii. p. 309. Equus 
Devillei, Gerv. 
Mr. Lund, the founder of tlie species, characterizes it by the greater 
breadth and flatness of the metatarse than any existing horse. The 
name macrognathus is founded on the greater length of the diastema 
in the Tarija specimens. The two lobes of the lower molars are more 
distinctly separated than in the E. cahallus, altliougli there is no inter- 
ruption in the ribbon of enamel. 
Castlenau calls attention to their more generalized type in the fol- 
lowing words: — " Before the crowns are worn, the thickness of the 
cement gives them a rather peculiar appearance, which makes them, 
up to a certain point, resemble those of Fhinoceros, because the arched 
form of each of their lobes is then more apparent, and because the 
ends of each curve are prominent in a tubercular form." 
Equus Devillii is not characterized by Lund, but Gervais figures a 
fragment of lower jaw, and an astragalus, the proportions of which 
are different from those of E. neogceus. The differences in the molar 
teeth are however very slight. 
Geog. Distrih. Tarija (Bolivia, Brazil). — Geol. Age. Pliocene. 
Equus Cuilensis. — Syn. Equus Americanus {Gay,\. 146). (Third 
lower molar, left side.) 
Characters. — Molars as large as those of Equus cahallus, and perhaps a little thicker : 
having the same general arrangement of enamel, dentine, and cement as it, but differing in 
some minor modifications. Thus, the conformation of the curves {las redondeces colo- 
cadas) attached to the inner border of the crown is somewhat more broad, and the 
space in the little isthmus which joins the first and second of these inner curves to the 
two oval ones outside, is also more broad and with plications less crenulated ifrisadu). 
(Gay, tuc. cit.) 
