THE CEPHALOPODA. 
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HI. — Shell lance-sliape, slender, with central keeled ridge, and side expansions of some 
length. Family, Gonatid^. One fossil genus, Loligo. 
5. LoLiGO, Lamarck, 1799. 
Lias sic. 
IV. — Shell lance-shape, subovate, with central ridge, and side expansions of some length. 
Pamily, Beloteuthid^. Pive fossil genera, Teudopsis, Phylloteuthis, Belo- 
teuthis, Geoteuthis, and Leptoteuthis. 
6. Teudopsis, Deslongchamps, 1835. 
Narrow at top, enlarged below, with a concavity at base, and narrow central rib ; 
Liassic into Oolite. 
7. Phylloteuthis, Meek and Hayden, 1858. 
Narrow at top, enlarged below, with slight concavity at base, where the lateral 
margins are obtusely angular ; Cretaceous. 
8. Beloteuthis, Miinster, 1843. 
Pointed at top and bottom, lateral expansions forming a sudden angle on the sides 
towards the lower half of total length ; Liassic. 
9. Geoteuthis, Miinster, 1843. = Belemnosepia, Agassiz, 1835. — Loligosepia, 
Quenstedt, 1839. = Coccoteuthis {pars), Owen, 1855. 
Wide at top, pointed at base, side expansions forming a sudden angle on the sides 
towards the upper half of total length ; Liassic. 
10. Leptoteuthis, von Meyer, 1834. 
Wide and rounded at top, pointed at base, lateral expansions gradually angular, 
ribs slight and diverging ; Oolitic. 
V. — Shell ovate, thick, with thin lateral projections, inclined to the sides, terminating in 
a projecting point imperfectly chambered. Family, Sepiad^ (Owen, 1836). 
One fossil genus. Sepia. 
11. Sepia, Linne, 1735. = Belosepia, Voltz, 1830. = Sepiolithes, Miinster, 
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