NEWTON AND HARRIS: BRITISH EOCKNE CEPHALOPODA. 123 



Soc. 1849, p. 36, pi. ii. figs, \a-\ff. J. de C. Sby.— 

 Dixon's "Sussex," 1850, p. 109, pi. ix. fig. 18. Desh.— 

 Desc. Anim. sans Yert. 1865, vol. iii. p. 619. 



Beloptera helemnoidea, R. B. Newton. — Syst. List Edwards Coll. 

 British Museum, 1891, p. 289. 

 In this species the lateral expansions are very pronounced, and are 



opposite the point of junction with the conical cavity. The rostrum 



becomes gradually larger for about two-thirds of its length, and then 



diminishes towards the extremity. Bare. 



Formation. — Bracklesham Beds. LocaUti/. — Bracklesham Bay and 



Bramshaw. 



Sub-genus Belopterina, Munier-Chalmas. 



Bull. Soc. Geol. France, 1872, ser. II. vol. xxix. p. 530. 



Type. — Beloptera Levesquei, Fer. and D'Orb., Hist. Xat. Ceph. 1840, 

 p. 295, pi. XX. figs. 11, 12. 



Differs chiefly from the typical forms of the genus in the absence of 

 true lateral expansions ; whilst its ventral surface is furnished with 

 an elevated, acute, and angular keel. 



Beloptera Levesquei, Ferussac and D'Orbigny. 



Beloptera Levesquei, Fer. and D'Orb. — Hist. Nat. Ceph. 1840, p. 295, 



pi. XX. figs. 11, 12. Edw.— Mon. Pal. Soc. 1849, p. 37, 



pi. ii. figs. 2a-2e. 

 Belopterina Levesquei, Mun.-Chalm. — Bull. Soc. Geol. France, 1872, 



ser. II. vol. xxix. p. 531. 

 Beloptera Levesquei, R. B. Newton. — Syst. List Edwards Coll. British 



Museum, 1891, p. 289. 

 Beloptera {Belopterina) Levesquei, Cossmann. — Ann. Soc. B. Mai. 



Belgique, 1892, vol, xxvi. p. 13. 

 The "lateral expansions" in this species are so rudimentary, being 

 in fact only elevated carinae, that certain French authors have denied 

 their existence. In other respects it closely resembles B. helemnoidea. 

 Very rare. 



Formation. — London Clay. ■ Locality. — Highgate. 



Genus SPIBULIROSTRA, D'Orbigny. 



Ann. Sci. Nat. Paris, 1842, ser. II. vol. xvii. [Zoologie], p. 374, 

 pi. xi. 



Belemnosis, Edwards. — Mon. Pal. Soc. 1849, p. 38. 



Belemnopsis, J. E. Gray. — Cat. Moll. British Mus. Ceph. Antepedia, 

 1849, p. 157. 



Type. — Spirulirostra Bellardii, D'Orb. Reference as above. 



Test consisting almost entirely of an enormous rostrum, furnished 

 in front with slight lateral expansions, and containing in the interior 

 a spiral shell, which is cylindrical and septated, the septa being 

 pierced on the inside by a continuous siphuncle. 



