Belemnites. 
MOLLUSCA. 
41 
O. Gesneri . Martin, Pet. Derby, pi. 38, fig. 1, 2. Fle¬ 
ming, Brit. An. p. 239. Phillips, Geo. of Yorkshire, II. 
p. 239, pi. 21, fig. 6. 
Shell curved, conical, with about thirty longitudinal, close, 
acute, regular ridges and rounded furrows; siphuncle placed 
nearly marginal ; section slightly ovate. 
Found in the Carboniferous Limestone of Derbyshire, 
Middleton Tyas, Northumberland ; Cumberland ; Isle of Man ; 
and Bolland, Queen’s County. 
19. O. rugosa. —The Rugged Orthocera, pi. XXVIII. 
fig. 8. 
Orthocera rugosa. Fleming, Brit. An. p. 239. ib. Ann. 
Phil. V. p. 203. Phillips, Geo. of Yorkshire, p. 239, pi. 21, 
%. 16. 
Shell subcylindrical, slightly arcuated with annular, undu¬ 
lating, somewhat distant ridges, crossed at intervals by strong 
strise producing a knotty appearance, the intervening spaces 
with longitudinal, tuberculated, subechinated lines ; siphun- 
culus minute, and situate close to the edge; between each 
of the transverse annulations are two chambers. 
Found in the Carboniferous Limestone of Northumberland. 
20. O. Cornu-Ibex. — The Ibex-IIorn Orthocera, pi. 
XXVIII. fig. 13. 
Orthoceras annulatum. Phillips, Geo. of Yorkshire, II. 
pi. 21, fig. 10. 
Shell a little arcuated, cylindrical, with many slightly 
undulous smooth annulations; intervening spaces smooth. 
This shell differs from the O. annulata in being more 
bent, in being greatly thicker in proportion to its length, and 
in the rings being closer. 
Found at High-Green-Wood. 
21. O. unguis. —The Claw Orthocera, pi. XXVIII. fig. 16. 
Orthoceras unguis . Phillips, Geo. of Yorkshire, II. p. 238. 
fig. 2. 
Shell smooth, abruptly arcuated towards the thicker end ; 
septa numerous ; section orbicular. 
Found at Bolland, Queen’s County, Ireland. 
22. O. dentaloideum. — The Tooth Orthocera, pi. 
XXVIII. fig. 18. 
Orthoceras dentaloideum. Phillips, Geo. of Yorkshire, II. 
p. 239, ph 21. fig. 12. 
Shell greatly curved, and tapering gradually, with nume¬ 
rous small longitudinal ridges and furrows. 
Found at Bolland, Queen’s County. 
Genus XI.—BELEMNITES.— Lamarck. 
Shell straight, conical, elongated, capable of being 
separated into two parts, the outer one a solid sheath, 
produced above, and excavated, with a conical cell 
beneath ; the inner nucleus conical, and multilocular, 
divided by numerous transverse septa, perforated by a 
central tube. 
SECTION. I.-SHELLS LANCEOLATE. 
1. B. lanceolatus. — The Spear-Shaped Belemnite, pi. 
XXIX. fig. 1. 
Belemnites lanceolatus. Sowerby, Min Conch. VI. p. 208, 
pi. 600, fig. 8, 9. 
Shell smooth, subfusiform, greatly elongated, one-hall' 
narrow, the other thickened, and gradually tapering to a 
point; each side with a double obsolete furrow ; base ob¬ 
scurely triangular, base convex, or conical. 
Found in the Chalk at Hamsev. 
2. B. gracilis. — The Slender Belemnite, pi. XXIX. 
fig. 13. 
Belemnites gracilis. Phillips, Geo. of Yorkshire, I. p. 138, 
pi. 5, fig. 15. 
Shell smooth, fusiform, thick at one end, and gradually 
tapering to a somewhat obtuse point, and extremely slender at 
the other ; section orbicular. 
Found in the Oxford Clay at Scarborough. 
3. B. attenuatus. — The Attenuated Belemnite, pi. 
XXIX. fig. 3. 
Belemnites attenuatus. Sowerby, Min. Conch. VI. p. 176, 
pi. 589, fig. 2. 
Shell subfusiform, somewhat quadrangular, tapering slightly 
towards the base, contracting abruptly a little above the 
centre, from which to the somewhat obtuse apex, it is nearly 
cylindrical, and frequently striated; each side is provided 
with an almost obsolete, double, longitudinal furrow, and a 
sulcus in front extending a short way from the base. 
Found at Folkstone. 
4. B. Allan i.—Allan’s Belemnite, pi. XXIX. fig. 8. 
Belemnites Allani. Fleming, Brit. An. II. p. 240. Belem- 
nite, Allan, Trans. Royal Soc. Edin. IX. p. 407, pi. 25. 
Mantell, Geo. of Sussex, p. 201, pi. 16, fig. 1. 
Shell smooth, cylindrical; apex conical, with a slender 
produced point; alveolus conical, acute, with a sublateral 
point; a longitudinal section exhibits a small tube extending 
from the alveolus to the apex of the spathose part. 
Found in Chalk at Brighton and Lewes. 
5. B. penicillatus. —The Pencil-shaped Belemnite, pi. 
XXIX. fig. 5. 
Belemnites penicillatus. De Blainville, Mem. sur les 
Belem, p. 89, pi. 3, fig. 7. Knorr, Part II. pi. 1,* fig. 1 to 4. 
Sowerby, Min. Conch. VI. p. 181, pi. 590, fig. 5, 6. 
Shell compressed, short, tapering in a very gradual man¬ 
ner towards the superior extremity, near which it is abruptly 
contracted to an almost central, longitudinally striated or 
sulcated obtuse point; cavity of the opposite extremity 
rather deep. 
Found in the Chalk in Sliorne Cliff. 
6. B. granulatus. — The Granulated Belemnite, pi. 
XXIX. fig. 6, 7 
Belemnites granulatus. De Blainville, Mem. sur les 
Belem, p. 63, pi. 1. fig. 10. Sowerby, Min. Conch. VI. p. 
207, pi. 600, fig. 3, 5. 
Shell subcylindrical; surface covered with small granula¬ 
tions, and the impressions of veins ; tapering rather abruptly 
to an obtuse mucronated apex ; sides with a double longitudi¬ 
nal nearly obsolete furrow. 
Found in the Chalk at Andover and Bridgewick Pit, near 
Lewes. It is said to occur in St Peter’s Mountain, near 
Maastricht. 
7. B. fusiformis. —The Spindle-Shaped Belemnite, pi. 
XXIX. fig. 14. 
Belemnites fusiformis. Parkinson, Org. Rem. III. p. 127, 
pi. 8, fig. 13. Fleming, Brit. An. p. 240. Phillips, Geo. of 
Yorkshire, I. p. 123, pi. 3, fig. 1. 
Fusiform, somewhat compressed in the fore part; abruptly 
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