26 
THE OEOLOGTST. 
Equus fossilis, v. Meyer, FalcBologica, Svo, 1832, p. 79. Owen, 
British Fossil Mamm. p. 383. 
The common British fossil horse, evidences of which are so com- 
mon in our bone caves and pliocene deposits, Professor Owen states 
to have been characterized by a larger head than the domesticated 
races ; resembling, in this respect, the wild horses of Asia described 
by Pallas, and in the same degree approximating the Tebrine and 
Asinine groups. He also points out that the second and third molars 
of both jaws are narrower transversely in comparison with their 
anteroposterior diameter than in the existing horse ; a character 
which, although present in the teeth derived from the Kirkdale Cave, 
Orestou, and the newer pliocene blue clay at Cromer, was absent in 
some of the Kent's Hole specimens. With respect to the more 
important characters of the degree and mode of plication of the 
enamel folds, no specific differences are demonstrated by Professor 
Owen between the E. fossilis and the F. cahalhis. The range of 
variation, however, amongst the existing horses, is as yet undeter- 
mined; and I purpose, at a future time, to institute an accurate com- 
parison, which would be, however, beyond the scope of the present 
paper. In Norway, I am told, on the authority of Mr. A. D. 
Bartlett, F.Z.S., that there still exists a breed of horses with traces of 
the zebra-striping on the legs. It would be a most fruitful source of 
information if the teeth of these horses were to be compared with 
those of the fossil European species ; and I doubt not but that the 
perseverance of the Superintendent of the Zoological Gardens will 
be crowned with success, in obtaining living specimens of this breed. 
Colonel Hamilton Smith divides the species JE. cahallus, or true 
horse, into four distinct origins : (a) the bay wild horse, or Tar pan ; 
(b) the white villous wild horse ; (c) the black wild horse ; (d) the 
Eelback, dun decussated. 
Characters. — Hitherto undetermined. 
Geog. Distrih. Northern Europe. — Geol. Age. Pliocene. 
Eqtjtjs PLiGiDEis^s, Oweii, Brit. Foss. 3famm. Sd^; Beport Brit. 
Ass. 231. (Eirst upper molar, second upper molar, right lower canine 
(juv.) astragalus, hoof phalanx.) 
Characters. — Enamel more complex than in E. cahalhis ; crown of last upper molar 
bilobed posteriorly, as in Hipparion, from which it differs in the form of the fifth or in- 
ternal ])rism of dentine in the upper molars, and in its continuation with the anterior 
lobe of the tooth, dilfering, like E. fossilis, from E. cahalltis, in greater anteroposterior 
diameter of crown of second, upper molar, and less produced anterior angle of first molar. 
(Owen.) 
Geog. Distrih. Oreston cave. — Geol. Age. Pliocene. 
Professor Owen says on this, " One cannot view the elegant fold- 
ings of the enamel in the present fossil teeth, and in those of the 
more ancient primigenial species {Hip pother id) of the Continental 
Miocene deposits, without being reminded of the peculiar character 
of the enamel of the molar teeth of the Elasmotherium, in which it is 
folded in elegant festoons." It is indeed a singular fact, altliough 
one accountable on a known biological law, that the more ancient 
