206 THE LIAS AMMONITES. 
1843. — Tracliyteuthis, Meyer, 1846. = Coccoteuthis, Owen, 1855. = Palseo- 
teutliis, Roeraer, 1856. 
Oolitic and Tertiary. 
VI. — Shell conical, slightly bent, having at its upper part a cavity containing chambers 
with a siphuncle. Family, Belemnosid/e. Eour fossil genera, Belemnosis, 
Beloptera, Helicerus, and Spirulirostra. 
12. Belemnosis, Edwards, 1849. 
Shell conical, and suddenly bent at a short distance from the base, no side expan- 
sions ; Tertiary. 
13. Beloptera, Deshayes, 1830. 
Shell conical, and slightly bent, side expansions at the angle ; Tertiary. 
14. Helicerus, Dana, 1849. 
Shell conical, the chambers at the upper part, slender and terminating in a spiral 
arrangement ; Liassic ? 
15. Spirulirostra, d'Orbigny, 1842. 
Shell conical, the chambers at the upper part, of some size and terminating in a 
spiral arrangement, the portion covering the commencement of the spiral projected for- 
wards, the extremity pointed ; Tertiary. 
VII. — Shell straight, with a series of conical chambers at its upper portion. Family, 
BELEMNiTiDiE (Oweu, 1836). Eive fossil genera, Belemnites, Belemnitella, 
Belemnoteuthis, Conoteuthis, and Xiphoteuthis. 
16. Belemnites, Lister, 1678. = Belemnitis lapis, Agricola, 1546. = Belem- 
nitis, Gesner, 1565. = Acamas, Montfort, 1808. = Hibolithes, Montfort, 1808. 
= Thalamus (= alveolus, &c.), 1808. = Actinocamax, Miller, 1823. = Pseudobelus, 
Blainville, 1827. = Belemnosepia, Buckland, 1836. = Belopeltis, Voltz, 1840 (a pro- 
ostracum). = Notosiphites, Duval- Jouve, 1841. = Gasterosiphites, Duval-Jouve, 
1841. 
Shell (guard) straight, generally long, somewhat cylindrical, conical below, with a 
hollow cone (alveolus) in the upper part, containing a chambered cone (phragmacone), 
