92 
SELACHII. 
(?) 1843. Pmmmodus corm/tug, J. E. Portlock, Rep. Geol. Londonderry, 
p. 461, pi. xiv. a, fig. 8. 
(?) 1855. Psammodus cornutm, F. M'Coy, Brit. Palaeoz. Foss. p. 643. 
1862. Copodus eornutus (Agassiz MS.), Morris & Roberts, Quart. Journ. 
Geol. Soc. vol. xviii. p. 100 (name only). 
1862. Copodus lunvdutm (Agassiz MS.), Morris & Roberts, loc. ci . 
p. 100 (name only). - 
1883. Copodus rornutm, J. W. Davis, Trans. Roy. Dublin Soc. [ J 
vol. i. p. 404, pi. Iviii. figs. 2-6 (non fig. 1). 
(?) 1883. Pinacodus gmoplax (Agassiz MS.), J. W. Davis, loc. cit. 
p. 477, pi. Iviii. fig. 22. 
Type. Detached teeth ; British Museum. 
Teeth mostly longer than broad; a curved transverse suture 
dividing the posterior fourth (or more) of the tooth from the ante- 
rior portion. The posterior border of the latter is excavated and 
gently curved, and the postero-lateral angles are not greatly prO" 
duced. The small isolated binder portion of the tooth has a sinuous 
posterior margin, strongly convex in the middle. 
It does not appear certain that the tooth originally figured y 
Portlock as pertaining to this species is the same as those upon 
■which the foregoing diagnosis is founded. It seems advisable, 
however, to follow Agassiz’s intentions as interpreted by J . W. Davis, 
who first fully defined the form. 
Form. Sf Loc. Lower Carboniferous Limestone : Armagh, Ireland , 
Northumberland (M‘Coy). Upper Carboniferous Limestone : York- 
shire. 
Unless otherwise stated, the following specimens are from the 
Enniskillen Collection. 
P. 2580-3. Four type specimens described and figured by J- 
Davis, loc. cit. 
P. 2584. Thirty-six examples of the main portion of the tooth. 
P. 2584 c. Similar specimen, showing a sinuous transverse suture 
near the anterior extremity. 
P. 2584 a. One small specimen, showing posterior portion of tooth 
in position, half as large as the anterior. 
P. 2584 h. Two detached examples of the posterior portion of the 
tooth. 
P. 1406-7. Six examples of the anterior portion of the tooth. 
Egerton CoU. 
26053-4, 38506. Eight similar specimens. Purchased, 1851, 1864. 
