206 THE LIAS AMMONITES. 



1843. = Trachyteuthis, Meyer, 1846. = Coccoteuthis, Owen, 1855. = Palaeo- 

 teuthis, Roemer, 1856. 



Oolitic and Tertiary. 



VI. — Shell conical, slightly bent, having at its upper part a cavity containing chambers 

 with a siphuncle. Family, Belemnosid^. Pour 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, 1843. 



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. Eamily, 

 Belemnitid^ (Owen, 1836). Five 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), 



