312 
yAUTILOIDEA. 
Horizon. Calsclaiste de Toui’nai (Assise i. e)\ = Carboniferous 
Limestone. 
Locality. Toumai, Belgium. 
Fairly well represented in the Collection. 
I ba\e decided, after some hesitation, to place the following 
species in the genus Cyrtoceras : — 
Cyrtoceras (Meloceras) scalpratum, J. de C. Sowerhy, sp. 
1840. Orthoceras scalpratian, J. de C. Sowerhy, Trans. Geol. Soc. 2nd 
ser. Tol. y. pt. iii. Explanation of plate xl. f. 3. 
1854. Orthoceras scalpratum, Morris, Cat. of British Foss. 2nd ed. p. 311. 
Hp. Char. “ Lanceolate, compressed, smooth [cast], slightly 
curved, with the edges angular, the inner one sharp ; septa nume- 
rous ; siphuncle small, near the obtuse edge.” (Sowerhy.) 
Rernarhs. This species is remarkably compressed, the ratio of the 
two diameters being about as 12 : 6. The curvature is very* slight, 
but quite perceptible. 
The only species in British rocks with which I can compare this 
one is the Cyrtoceras corapressum of J. de C. Sowerhy, but the latter 
has a much greater curvature. 
Horizon. Wenlock. 
Locality. Coalbrookd^e \ Shropshire. 
Bepresented in the Collection by three specimens. 
Subgenus OOCERAS, Hyatt, emend. Foord. 
This subgenus includes very slowly tapering, laterally compressed, 
elongated shells, with very short body- chambers. The cross section 
is ovate, the narrower end corresponding with the outer or ventral 
curvature of the shell. The siphuncle is usually external (exo- 
gastric) ; rarely internal (endogastric).— Ordovician to Devonian. 
OBDOVICIAX SPECIES. 
^ Exogastric. 
Cyrtoceras (Ooceras) falcatxim, Schlotheim, sp. 
1820. Orthoceratites falcatus, Schlotheim, Petrefactenkunde p. 53. 
1822. Orthoceratites falcatus, Schlotheim, Xachtrage z. Petrefacten- 
kunde, Abth. i. p. 58, Taf. viii. ff. 2, a, h. 
^ See ante, p. 54. 
® The Plates illustrating this work are dated 1832. 
