306 
NATJTILOIDEA. 
Sjp, Char. Shell very slightly curved. Section nearly circular. 
Eate of increase about 1 in 4. Septa distant from each other 1| 
line where the diameter of the shell is 9 lines. Siphuncle close to 
the convex border. Test apparently smooth. 
Horizon. Iberger-Kalk ; Upper Devonian. 
Locality. \Yinterberg, North-western Hartz. 
Eepresented in the Collection by a single example. 
Cyrtoceras (Meloceras) subrugosum, d’Orbigny, sp. 
1849. Cyrtoceras suhrugosum, d’Orbigny, Prodr. de Pal^ont. Stratigra- 
phique, vol. i. p. 53. 
/Sp. Char. D’Orbigny gives the following description of his species: — 
“ Espece en come ronde, pen allouge'e, arquee, pourvue de rides 
transversales irregulieres. Cloisons tres-obliques.” 
The curvature of the shell is moderate. The rate of increase is 
probably about 1 in 4. The septa, which are very oblique, are 
distant from each other about 1| line upon the convex border of the 
shell, where the latter has a diameter of 10 lines. The ornamen- 
tation consists of irregularly spaced transverse riblets, which have 
a tendency to run in pairs ; they form a very shallow sinus on the 
convex border of the shell. Very faint close-set longitudinal lines 
may also be seen, if the specimens be held in a good light. The 
siphuncle is situated close to the convex border ; its internal struc- 
ture is not seen. 
RemarTcs. I can find no mention of this species in any of the 
numerous memoirs in the Soc. Ge'ol. du Nord, or other Erench geolo- 
gical journals. Messrs, de Tromelin and Lebesconte ^ in an enu- 
meration of Devonian fossils of the “ gres de Gahard ” mention that 
“ several species ” of Cyrtoceras are found therein, but they make 
no attempt to name them. 
Horizon. Lower Devonian 
Locality. Nehou (Manche), Prance. 
Eepresented in the Collection by three fairly good specimens. 
CAEBONIPEEOUS SPECIES, 
a. Exogastric. 
Cyrtoceras (Meloceras) cornu, de Koninck, sp. 
1829. Orthocera fusiformis, J. de C. Sowerby, Min. Conch, vol. vi. 
p. 167, tab. dlxxxviii. f. 2 (excl. f. 1). 
^ Soc. Geol. de France, ser. 3, vol. iv. 1876, footnote, p. 614. 
^ I give this horizon on the authority of de Tromelin, — Assoc. Pran 9 . 6me 
Sess. Havre, 1878, p. 493, — “ Terr. Paleoz. de Normandie.” 
