424 On the Fossil Fishes of the Carboniferous Limestone Series of Great Britain. 
Streblodus oblongus, Agass. (MSS.) 
(Pl. LIIT., figs. i-4.) 
Cochliodus oblongus—L. Agassiz, 1838, “Rech. sur les Poiss. Foss.,” Vol. III., p. 174, indet. 
55 3 J. E. Portlock, 1843. “Rept. on Geol. Londonderry, &c.,” p. 466, pl. 
xiva, figs. 5, 10. 
5 C. G. Giebel, 1848. “Fauna der Vorwelt,” Vol. L., part iii., p. 336. 
x ry; H. G. Bronn, 1848. “ Nomencl. Paleont.,” p. 317. 
5 5 H. G. Bronn, 1849. “ Enumerator Paleont.,” p. 647. 
¥ ‘i J. Morris, 1854. “Cat. Brit. Foss.,” p. 322. 
35 Pa F. J. Pictet, 1854. “ Traité de Paléont.,” Vol. II., p. 267. 
i Ps F. M‘Coy, 1855. “Brit. Paleoz. Foss.,” p. 623, pl. 3 H, fig. 19, and 
pl. 3 L., fig. 28. 
Streblodus oblongus—L. Agassiz, 1859. “ MSS., Enniskillen collection.” 
9 Morris & Roberts, 1862. “ Quart. Journ. Geol. Soc.,” Vol. XVIII., p. 101. 
” R. Owen, 1867. “Geological Magazine,” Vol. IV., p. 62, pl. m1, 
fig. 3. 
5 55 Enniskillen, 1869. “Catalogue Type Spec. Foss. Fish.,” p. 8 
% 3 J.J. Bigsby, 1878. ‘Thesaurus Devonico-Carb.,” p. 365. 
“ Posterior tooth elongate, narrow, sub-cylindrical, oblong, obliquely sub-truncate, 
elliptically pointed at about an angle of 45° behind; anterior margin nearly at 
right angles to the long axis of the tooth; anterior ridge very small, almost ob- 
solete, scarcely defined from the equally wide flattened space between it and the 
second oblique ridge, which is strongly defined on each side, but narrow and only 
moderately convex ; posterior ridge very large, exceeding twice the width of the 
middle ridge, separated from the middle one by a broad, moderately concave 
sulcus, rather more prominent than the middle ridge, broadly and moderately 
convex, abruptly rounded at its anterior edge, but gradually sloping towards the 
posterior end; length of rathen small specimens about one inch two lines, of 
middle ridge only two lines.” —(/‘Coy.) 
Since the above description was penned a specimen has been found, consisting 
not only of the posterior teeth, but also of two smaller teeth on each side of the Jaw, 
placed anteriorly to those described by M‘Coy (see Pl. LIIL, fig. 1); the teeth are 
somewhat broken and badly preserved, and the parallel position in which they are 
now placed is not the natural one, otherwise this unique specimen is extremely 
valuable in affording information as to the position and character of the dental 
apparatus of the fish. The jaw preserved appears to be the lower one, and consists 
of a pair of the large posterior teeth, described by Prof. M‘Coy, one on each ramus 
of the jaw—two inches in length and °8 inches in breadth. In front of these are 
two teeth, much smaller and not very characteristically defined in this specimen. 
The second tooth is about one-third the length of the large posterior one, and 
equal in breadth to its length. It is sub-globose in outline, the posterior margin 
flattened where attached to the contiguous tooth ; anterior margin also compressed 
for attachment to the smaller anterior tooth. Crown surface obliquely convex, 
