On the Fossil Fishes of the Carboniferous Limestone Series of Great Britain. 475 
The genus Characodus may be distinguished from Rhymodus by the absence of 
the deeply-concave anterior margin, and the crescent-shaped portion of the crown, 
which is occasionally found occupying the concavity ; and from Labodus by its 
coneaye or straight posterior margin and prominent base ; this margin in Labodus 
being deeply convex, and extending considerably beyond the basal posterior margin. 
Characodus angulatus, Agass. MSS. 
(PL TUN UUL, syeys, IN)5 AOE) 
Characodus angulatus—bL. Agassiz, 1859. MSS. Enniskillen Coll. 
Ps Morris and Roberts, 1862. ‘“ Quart. Journ. Geol. Soc.,” Vol. XVIITI., p. 99. 
ik - Enniskillen, 1869. ‘‘ Cat. Type Spec.” p. 3. 
Fe 5 J. J. Bigsby, 1878. ‘Thesaurus Dey.-Carb.,” p. 349. 
Teeth, trapezoidal in outline, medium size, posteriorly about an inch in breadth, 
half an inch in length; crown, central portion longitudinally and transversely con- 
vex. Each lateral border is considerably raised above the central coronal area ; 
surface coated with enamel and deeply punctured ; front part of the crown gene- 
rally worn by attrition ; anterior margin two-thirds the breadth of the posterior, 
straight or slightly convex ; lateral margins straight, augmenting in breadth pos- 
teriorly ; the enamel and the osseous basal portion co-extensive, flat ; posterior 
margin parallel to that of the anterior, straight or slightly concave ; postero-lateral 
angles produced backwards in a line with the side, acuminate, raised prominently 
forward. Base not well exposed ; retreats from the anterior margin of the crown, 
and extends slightly beyond the posterior one. ‘Hhe tooth is about -2 of an inch 
thick. 
Formation and locality: Mountain Limestone, Armagh, 
Ex coll. Earl of Enniskillen. 
Characodus cuneatus, Agass. MSS. 
(P), LVL, fig. 21.) 
Characodus cuneatus—L. Agassiz, 1859. MSS. Enniskillen Coll. 
5 Morris and Roberts, 1862. ~“‘ Quart. Jour. Geol. Soc.,” Vol. XeVALI 99: 
5 5 Enniskillen, 1869. ‘Cat. Type Spec.,” p. 3. 
99 % J.J. Bigsby, 1878. ‘Thesaurus Dev.-Carb.,” p. 349. 
Teeth, inversely conical or cuneiform in outline, “7 of an inch in breadth across 
the posterior border, diminishing to *5 of an inch anteriorly. The length of the 
tooth is 6 of an inch. Crown, longitudinally deeply convex ; the anterior portion 
more curved than posterior ; transversely concave, the lateral borders produced, 
forming ridges of unequal width; surface enamelled, punctate ; two or three broad 
indistinct plications extend transversely across it; front part hollowed by attrition ; 
anterior margin slightly concave ; ganoine infolding base and crenate ; antero- 
lateral angles right angles; lateral margins straight, crenulated, ganoine thick, 
and infolding to some extent the osseous base ; posterior margin slightly convex ; 
