466 On the Fossil Fishes of the Carboniferous Limestone Series of Great Britain. 
specimens, which, rendered necessary to the proper fitting of their respective 
surfaces, affords an additional proof of the identity of the species. 
Formation and locality : Carboniferous Limestone, Armagh ; tolerably common. Rare in the dark 
Lower Limestone at Lowick (M‘Coy). 
Ex Coll. Earl of Enniskillen. 
Copodus furcatus, Agass. MSS. 
(Pl. LVIIL, fig. 16.) 
Copodus fureatus—L. Agassiz, 1859. MSS. Enniskillen Collection. 
es falcatus (?)—Morris and Roberts, 1862. “ Quait. Journ. Geol. Soc.,” Vol. XVII, p. 100. 
Pe furcatus—Enniskillen, 1869. “Cat. Types Fossil Fish,” p. 4. 
3 falcatus (?)\—J. J. Bigsby, 1878. ‘Thesaurus Devonico Carb.,” p. 354. 
Teeth, sub-quadrate, deeply forked posteriorly ; breadth, ‘8 of an inch, length, 
‘9 of an inch from the anterior margin to the extremity of the fork; along the 
median line to the point of bifurcation the length is ‘7 of aninch. Crown, convex, 
with lateral margins raised, forming a slight, longitudinal concavity along each 
side ; convexity in antero-central part much abraded by use. Posteriorly, the 
coronal surface is depressed along the median line, prior to the bifurcation. The 
surface is coated with enamel, and pierced by mnumerable irregularly-disposed 
punctures. Anterior margin straight in middle, with obtusely-rounded corners. 
Laterally, the crown is nearly straight to the extremity of the postero-lateral 
angles, where the diameter is slightly contracted. The postero-lateral are formed 
by the posterior margin, which makes an acute angle with the lateral ones on each 
side, and meeting in the median axis of the tooth, constitutes an approximate 
right-angled bifurcation. Base equal in size and same form as the crown, charac- 
terized by the ordinary structural appearance. 
This species offers some resemblance to C. cornutus. The form of the 
anterior portion of the tooth is very similar, but the posterior is quite distinct. 
The bifurcation from the centre of the tooth in this species forms a specific 
difference which cannot be mistaken. The pittings in the coronal enamel of 
C. furcatus are less distinct, and separated by wider expanses of enamel than in. 
any other species of this genus. 
Formation and locality : Mountain or Carboniferous Limestone, Armagh, Ireland. 
Ex coll, Earl of Enniskillen. 
