BKUNIQUEL, AND ITS ORGANIC CONTENTS. 
543 
ness, and that to a degree greater than in Horse or Ass. The fore part of the upper 
grinding series bends inward more than in any of the foregoing Equines. 
In the lower series of grinders (fig. 2) the outer longitudinal fold, i, is less complex 
than in the Ass, less deep than in the Kiang, still less so than in the Horse ; the antin- 
ternal fold, Jc, is more complex, in p 2 and p 3, than in Horse, Ass, or Kiang. The ter- 
minal expansion of the fold g is wider, in the transverse direction of the tooth, than 
in the foregoing Equines. In the proportional extent of the premolars the Quagga 
agrees with the Kiang and Ass. 
Equus Burchelli. — The subjects of Plate LIX. figs. 3 & 4, are from the skull of a full- 
grown female Dauw, from Caffraria, in the British Museum (No. 854 a). 
On the right side of the upper jaw (fig. 3), the rudimental representative of 1 in Ilip- 
parion and PalceotJierium is retained, situated on the inner side of the anterior lobe or 
production of p 2, close to the fold Jc *. 
In the pattern and proportions of the upper molar series the Dauw closely resembles 
the Quagga. The grinding-surface of the last molar, m 3, has the well-marked bilobed 
termination : but the longitudinal channels, /' f, of the antecedent grinders are more 
regularly concave, and the lobes a, b (in fig. 13, p 3) are more crescentic. The ridge n, 
as in the Kiang, Quagga, and Ass, is narrower, more simple, and more produced than in 
the Horse. The lobe m, in m 1 and m 2, is thicker transversely, and makes that side of 
the tooth more convex or prominent. The fore part of this lobe is less produced than 
in the Kiang. 
In the lower molars (fig. 4) the terminal expansion of the fold Jc is less complicated 
with secondary foldings than in the Quagga, at least in p 3 and p 4, the Dauw in this 
particular resembling the Kiang and the Ass. The mid internal fold, f is deeper and 
more angular than in the Kiang. 
Equus zebra. — The drawing of the grinding-surface of the right upper molar series 
(Plate LX. fig. 1) is from the skull of a young full-grown male Zebra, from South Africa, 
in the British Museum (No. 706 b ), showing a phase of dentition answering to that 
between the fourth and fifth year in the Horse. The last premolar, p 4, is just attaining 
the level of p 3 and m 1 ; the summits of the inner lobes, c, d, are beginning to be abraded, 
as are those those of their productions, m, o — the former showing the condition of the 
detached enamelled lobule which, by its longer retention of the insular character, is 
characteristic of the Hipparion’s molars. The last molar, m 3, has cut the gum, but 
not reached the grinding-level. This tooth, so seen, presents a smaller relative size than 
in the Ass ; but when abrasion and growth shall have brought a larger part of the crown 
* In my ‘ Odontography ’ this denticle is described as follows : — “ The first deciduous molar is very minute, 
and is not succeeded, as in the Anoplothere, by a permanent premolar ; yet remaining longer in place than the 
largest deciduous molars behind, it represents the first premolar, and completes the typical number of that divi- 
sion of the grinding series” (p. 572). Accordingly, to facilitate the comparisons with Hipparion, Palseotherium, 
and Anoplotherium, this denticle is marked p 1 in the Plates — a circumstance which has led to inference and 
comments which reference to the text would have shown to be groundless. 
4 d 2 
