510 On the Fossil Fishes of the Carboniferous Limestone Series of Great Britain. 
apex ; punctured surface terminating below ina notch, or arched line, the convexity 
upwards ; root long, as wide as crown, coarsely fibrous.—(M* Coy, Ann. Nat. Hist.,. 
Second Series, Vol. II., p. 127.) 
A number of teeth of considerable diversity of form appear to be included in the 
above generic description. It is difficult, however, to distinguish amongst them 
specimens which exactly supply the characters ascribed by Prof. M‘Coy to Glossodus 
lingua-bovis described in the volume of the Magazine of Natural History referred 
to, but not figured. The majority of the specimens belong to the species 
G. marginatus, M‘Coy, also described in the Mag. of Nat. History, and afterwards 
figured in Brit. Paleoz. Foss., p. 629 Pl. 3 k., fig. 1. The latter, it is stated, 
may be easily distinguished frorn G. lingua-bovis by its more finely punctured, glossy 
surface, rounded tip and prominent lateral margins. These characters are 
possessed to a large extent by all the specimens, and those applied in the 
discrimination of G. lingua-bovis, viz., of possessing a dull surface, the antero-posterior 
diameter being only equal to half the width of the base, and the latter three times 
the width of the truncated apex, do not appear to be characteristic of any of the 
specimens. It is probable that all may belong to the same species, and as. 
G. marginatus has been figured and redescribed by Prof. M‘Coy, whilst C. lingua- 
bovis was not transferred forward to the Brit. Palzeoz. Fossils, it will be preferable 
to retain the former specific name—though, as will be presently explained, the 
species will include a much wider variety than was contemplated by Prof. M‘Coy. 
Glossodus marginatus, M‘Coy. 
(Pl. LXL., figs. 3, 8a, 3b, 4, 5, 5a.) 
Glossodus marginatus—F. M‘Coy, 1848. “Ann. & Mag. Nat. Hist.,”Ser. 2, Vol. IT., p. 128. 
»  lingua-bovis, ‘5 1848. ee 9 3 Ser. 2, Vol. II., p, 127. 
ms F. J. Pictet, 1854. “Traité de Paléont.,” Vol. II., p. 259. 
» marginatus, 5 1854. 4 5 Vol. IL., p. 259. 
. a J. Morris, 1854. “Catal. Brit. Foss.,” p. 327. 
»,  lingua-bovis, se 1854. = " p- 327. 
»  marginatus—F. M‘Coy, 1855. ‘Brit. Paleoz. Foss.,” p. 629, pl. 3 K., fig. 1. 
- x Morris and Roberts, 1862. ‘Quart. Journ. Geol. Soc.,” Vol. XVIII, p. 100. 
5,  lingua-bovis, ss * 1862. 5 5 35 Vol. XVIII, p. 100. 
»  marginatus—Young and 1871. “Trans. Geol. Soc., Glasgow,” Vol. III., Supt.,. 
Armstrong, fm Jl 
2 2 Armstrong, Young, 1876. “Catal. of W. Scot. Fossils,” p. 61. 
and Robertson, 
», _ lingua-bovis—J. J. Bigsby, 1878. ‘Thesaurus Devonico-Carb.,” p. 355. 
» marginatus, 5S 1878. 3 5 p. 359. 
Teeth, varying from 1 inch to ‘2 inch in length; average example ‘7 inch in length, 
‘25 inch across the base of the crown, and converging toan apex more or less shaped 
like a tongue, or in some instances much more acuminate—diameter from back to. 
front equal or greater than the width of the base. The crown is elevated and 
