On the Fossil Fishes of the Carboniferous Limestone Series of Great Britain. 405 
Lophodus gibberulus, Agassiz (sp.) 
(PI. LI., fig. 19.) 
Psammodus gibberulus—L. Agassiz, 1838. ‘‘Poiss. Foss.,” Vol. IIL, pl. xii, figs, 1, 2. 
“ F P. de G. Egerton, 1837. “Cat. of Fossil Fishes.” 
Helodus t, L. Agassiz, 1838. ‘“ Poiss. Foss.,” Vol. IIL, p. 106. 
os 5 J. E. Portlock, 1843. “Geol. Rept. Londonderry, &c.,” p. 461. 
3 an C. G. Giebel, 1848. ‘Fauna der Vorwelt,” Vol. L., pl. 3, p. 340. 
ss - H. G. Bronn, 1848. “Nomencl. Palont.,” p. 583. 
4 . . 1849. ‘Enumerator Paleont.,” p. 647. 
33 . J. Morris, 1854. “Cat. Brit. Foss.,” p. 328. 
a 5 F. J. Pictet, 1854. “Traité de Paléont.,” Vol. II. p. 267. 
s oy E. d’ Eichwald, 1860. ‘ Lethea rossica,” Vol. I. p. 1546. 
. an Morris and Roberts, 1862. “ Quart. Journ. Geol. Soc.,” Vol. X VIIL., p. 100. 
5 : J. J. Bigsby, 1878. ‘Thesaurus Devon.-Carb.,” p. 357. 
Lophodus 5 L. G. de Koninck, 1878. “Fauna du Calc. Carbon. de la Belgique,” 
p. 35. pl. iv., fig. 7. 
Teeth, broadly elongated, crown elevated into two cones; length °65 inch, 
breadth -25 inch, height of central cone ‘25 inch. Crown; central cone obtusely 
rounded, anteriorly depressed, longitudinal surface produced so as to form a 
ridge like prominence. A deep sulcus separates the central cone from a smaller 
one on the left side which partakes generally of the characters of the larger 
elevation ; the lateral extremities of the coronal surface are obtuse, about the same 
breadth as the base of the central cone, and are recurved upwards producing the 
appearance of a small cone one on each side. Anterior surface slightly convex, and 
one-third deeper than the posterior. Coronal surface enamelled, smooth along the 
apex, deeply punctate elsewhere. Base large, extending laterally beyond the 
surface of the crown; anteriorly it descends obliquely with the surface of the 
crown, posteriorly it is deeply concave; roughly striated and fibrous; a ridge 
extends along the anterior and posterior surfaces separating the crown from the 
base, it is occasionally slightly serrated. Specimens found in the Limestone of 
Belgium, and ascribed to this species by M. de Koninck, are stated to have both 
lateral extremities with an equal number of secondary cones, in this respect 
differing shghtly from those described above. 
The type specimen figured by M. Agassiz in the “ Poissons Fossiles” is slightly 
imperfect at one extremity. It is from the Limestone of Bristol. 
Formation and locality ; Mountain Limestone, Armagh ; Bristol ; Yorkshire. 
Ex coll, Earl of Enniskillen. 
