ACTD^OCEEATID^. 
. 187 
Horizon. Niagara Group (Wenlock). 
Locality. Drummond Island, Lake Huron. 
Eepresented by the type specimens figured by Stokes. 
DEVONIAN SPECIES. 
Actinoceras striatum ?, Sowerby, sp. 
{Infra, p. 190.) 
Cf. Orthoceras Ludense, Phillips, Pal. Foss, of Cornwall &c., 1841, 
p. 110, pi. xlii. if. 206, a-c, {Not of Sowerby.) 
To this species I refer, with a considerable degree of doubt, a 
large specimen from Lower Dunscombe, because many essential 
specific characters are lacking in it. The shell is completely devoid 
of test, and the septa can only be obscurely made out. The shell is 
elliptical in section, the ratio of the two diameters being as 29 : 34. 
The rate of increase measured along the broader diameter is about 
1 in 9. The septa are apparently distant about 8 lines, where the 
shell has a diameter of about 2 inches. 
Prof. M‘Coy says that he has “ little doubt that the S. Petherwin 
and Marwood shell, referred by Prof. PhiUips to the Silurian 
0. Ludense, belongs to this sj)ecies ” [i. e. A. striatum, Sowerby, sp.]. 
Horizon. Lpper Devonian (Intumescens Stage). 
Locality. Lower Dunscombe, near Chudleigh, Devonshire. 
Eepresented in the Collection by one example presented by 
J. E. Lee, Esq., E.G.S. 
CAEBONIEEEOUS SPECIES. 
Actinoceras giganteum, Sowerby, sp. 
1821. OHhocera gygantea, J. Sowerby, Mineral Conch, vol. iii. p. 81, 
tab. ccxlvi. 
1825. Orthoceratites giganteus, Defrance, Diet, des Sciences natureUes, 
tom. xxxvi. p. 484. 
1826. Orthoceratites giganteus, d’Orbigny, Tab. meth. de la classe des 
Cephalopodes, p. 72. 
1828. Orthocera gigantea, Fleming, Hist, of British Animals, p. 239. 
? 1829. Orthoceratites lolyphemus, Fischer, Bull, de la Soc. Imp. des 
Naturalistes de Moscou, p. 322. 
? 1832. Orthoceredites Folyphemus, Goldfuss, in H. von Dechen’s transl. 
of H. T. de la Beche’s Handb. of Geology. 
1836. Orthoceras giganteum, Phillips, Geol. of Yorkshire, pt. ii. p. 237, 
pi. xxi. f. 3. 
