322 BRITISH PALAOZOIC FOSSILS. [CepHALopopa. 
OrTHOCERAS (Poterioceras) PYRIFORME (Sov. Sp.) 
Ref. and Syn. < Orthoceras Id. Sow. Sil. Syst. t. 8. f. 19. (upper, but not lower figure). 
Sp. Ch.—Pyriform, greatest width about halfway between the last chamber and the mouth, curving abruptly 
thence to the contracted mouth, and tapering conically to the extremity of chambered portion; septa with a 
slight obliquity, the last three or four being about three lines apart; greatest diameter of last chamber two 
inches nine lines, length of last chamber the same; apical angle about 40°. 
See Poterioceras ellipticum, for observations on the allied species. 
Position and Locality —Lower Ludlow rock, near Aymestry, Herefordshire. 
Genus. PHRAGMOCERAS (Brod.)* 
Gen. Char.—Shell short, arched, compressed ; sides of the mouth lapping towards each other; septa 
simple, crossed by the sigmoidal lines of growth; siphon on the internal edge, dilate between the septa. 
I think it is very doubtful whether the opening of the shell is naturally contracted as much as usually 
represented, the form of the lines of growth and the appearance of such mouths as I have seen gives rather 
the idea of the edges being very thin and fiexible, yielding easily to compression. M. d’Orbigny (Prodrome) 
refers this to Campulites of Deshayes, contrary to the express declaration of that author (Lam. Hist. Nat. 
Anim. S. Vert. 2nd edition, p. 53), who states Campulites on the contrary to be identical with Cyrtoceras 
(Gold.) + Gyroceras (V. Mey.) 
PHRAGMOCERAS INTERMEDIUM (J/‘Coy). 
Ref. and Syn.—Id. M°Coy, Ann. Nat. Hist. 2nd Series, Vol. VII. p. 45. < Phragmoceras arcuatum 
Sow. Sil. Syst. t. 11. f. 1. (mot t. 10. f. 1a.) 
Sp. Oh.—Slightly arched, tapering at the rate of four lines in one inch; section ovate, sides gently convex, 
outer and inner faces rounded. A specimen (not quite perfect) two inches five lines long, has the long (antero- 
posterior) diameter at the large end one inch four lines, at the small end nine lines, short (lateral) diameter at 
large end ten lines, length of last chamber one inch one line, the last five or six septa one and half lines apart 
in the middle of the side. 
I have not clearly seen the siphon of this species, which is about as thick and slightly arched as the 
P. arcuatum (of which it is figured as a separate variety by Sowerby), but tapers much more slowly, as in the 
P.. compressum. 
Position and Locality —Green mudstone (Lower Ludlow) of Green Quarry, Leintwardine, Shropshire. 
PHRAGMOCERAS VENTRICOSUM (Sow.) 
Ref—Sow. Sil. Syst. t. 10. f. 4, 5, 6. 
Sp. Ch.—Gently arched, compressed, sides gently convex, most so in the last chamber ; septate portion 
more flattened ; antero-posterior diameter at last septum (and of last chamber) about three inches, width at 
same point one inch six lines; chambered portion tapering at the rate of eight lines in one inch (the length 
being taken along the middle of the side and the diameter along the septa); length of last chamber three 
inches, length of septate portion (measured along the convexity of the curve) about six inches; last few septa 
four lines apart (in middle of side) ; sigmoidal lines of growth crossing the septa, close, cord-like, about three 
or four in a quarter of an inch. 
The septa have a slight sigmoid wave on each side; the siphon is indistinct in the specimens before me. 
The published figures do not indicate sufficiently the flattening of the septate portion. 
* This, and the remaining genera or subgenera haye been omitted in the list at the end of the article Nautilidc, but 
Phragmoceras, Hortolus, and Lituites, should be placed near Cyrtoceras, and Trocholites near Clymenia. 
