322 
ACTINOPTERYGII. 
Genus HEXAPSEPHUS, Gunther. 
[Geol. Mag. (2) vol. hi. 1876, p. 439.] 
An extinct genus known only by the pharyngeals and dentition. 
Pharyngeal bone falciform, bearing a single series of large, stout, 
conical or mammilliform teeth, few in number. 
/ Hexapsephus guentheri, sp. nov. 
1876. Hexapsephus sp., A. Giinther, loc. cit. p. 439, pi. xvi. figs. 2, 3. 
Type. Pharyngeal; British Museum. 
The type species, with pharyngeal attaining a length of 0*026. 
Only three large pharyngeal teeth in close series; foremost tooth 
smallest, much laterally compressed; middle tooth having crown 
surmounted with two small longitudinal ridges, of which the outer 
is divided by a notch into two tubercles; hindermost tooth conical, 
with apex excentric. 
Forwt. Loc. Freshwater Tertiary Formation : Padang, Sumatra. 
47534. Pharyngeal with dentition, the type specimen described 
and figured loc. cit. p. 439, pi. xvi. figQ; in carbonaceous 
shale. Presented hy Herr^^^yV. M. Verheek.^ 1876. 
47533,-35. Two sets of pharyngeal teeth, one figured loc. cit. 
pi. xvi. fig. (3-, also four detached pharyngeal teeth, and 
two small slabs of carbonaceous shale with other teeth. 
Presented hy Herr B. D. M. Verheek.^ 1876. 
Several detached pharyngeal bones and teeth of Cyprinid® from 
a freshwater Upper Tertiary formation in Idaho have been described 
as follows :— 
Diastichus macrodon, E. D. Cope, Proc. Amer. Phil. Soc. vol. xi. 
(1870), p. 539, and Proc. Acad. Nat. Sci. Philad. 1883, 
p. 158. [Type species.] 
pcirvidens.^ E. D. Cope, loc. cit. 1870, p. 540. 
C P ‘ ^ Diastichus strangulatus^ E. D. Cope, loc. cit. 1883, p. 158. . / a 
, — Leucus condoniayius, E. D. Cope, loc. cit. 1883, p. 156.', 
Leucus latus, E. D. Cope, loc. cit. 1883, p. 156. Anchyhopsis 
latus, E. D. Cope, loc. cit. 1870, p. 543. [Type species 
of so-called Anchyhopsis.^ 
Mylocyprinus injlexus, E. D. Cope, loc. cit. 1883, p. 154. 
Mylocyprinus rohustus, J. Leidy, Proc. Acad. Nat. Sci. Philad. 
1870, p. 70, and Contrib. Extinct Yert. Fauna W. Territ. 
(Eep. U.S. Geol. Surv. Territ. vol. i. 1873), p. 262, 
pi. xvii. figs. 11-17; E. D. Cope, Zoc. 1883,-p. 155. 
Includes M. kingi and M. longidens, E. D. Cope, loc. cit. 
