598 MOLLUSCA , SUB-KINGDOM VI 
Diploconus, Zitt. (Fig. 1244). Guard short, obtusely conical, and having a con- 
centric lamellar structure, not radial and fibrous. Phragmocone reaching nearly to 
posterior end of guard. Tithonian. 
Bayanoteuthis, Mun.-Chalm. Guard long, cylindrical, mucronate, with shallow 
lateral grooves. Dorsal area roughened. Phragmocone very slender and long, oval in 
section. Eocene. B. rugifer, Schloenb. 
Vasseuria, Mun.-Chalm. Guard slender, elongated-conical, with three longitudinal 
grooves extending from the apex. Alveolus over half as long as the guard. 
A B 

Fic. 1244. 
Diploconus belem- 
nitoidea, Zittel. Ti- 
thonian ; Stramberg,. 

Fic. 1242. 

Belemnites (Actinocamax) quad- 
ratus, Bly. sp. Upper Creta- 
ceous; Germany. <A, Dorsal ‘ REC 
view of guard with deformed ee aie oS 
phragmocone projecting from Belemnites (Belemnitella) mucronatus, Beloptera belem- 
alveolus. B, Ventral aspect of Schloth. Upper Cretaceous; Drenstein- nitoidea, Bly. Caleaire 
guard. C, Alveolus from above furth, Westphalia. A, B, C, Ventral, dorsal, Grossier ; Paris Basin. 
(after Schluter). and lateral aspects. 2/3. Ventral aspect. 
Siphonal funnels extending from one septum to the next. Very rare in Eocene of 
Pretagne. 
Belemnosis, M. Edw. Very rare in English Eocene. 
Beloptera, Blainy. (Fig. 1245). Guard short, composed of two cones placed with 
their apices against one another and united by a central expansion which projects 
outwardly on either side. Anterior cone with alveolus. Phragmocone unknown. 
Eocene, 
Belopterina, Mun.-Chalm. Like Beloptera, but without the lateral wing-like 
expansions. Eocene. 
Family 2. Belemnoteuthidae. Zittel. 
Shell composed of a conical phragmocone and proostracum, the rostrum being reduced 
to a thin calewreous investment of the phragmocone. Ten arms of nearly equal length, 
each beset with a double row of hooks. Ink-sac present, Trias and Jura. 
