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CATALOGUE OF CEPHALOPODA. 
Synopsis of Genera. 
A. Tentacular and sessile Arms with claw ‘like Hooks. 
1. Enoploteuthis . — Fins subterminal, dorsal, rhombic. Sessile 
arms with hook only. Shell pennate, lanceolate. 
2. Ancistrocheirus. -—Fins occupying the whole side of the back, 
rhombic. Sessile arms with hooks only. Shell dilated at each 
end. 
3. Abralia.— Fins subterminal. Sessile arms with hooks at the 
base and cups at the tip. Shell lanceolate, concave on the 
edges. 
4. Octopodoteuthis. — Fins on the hind part of the back, roundish. 
Shell narrow. 
5. Acanthoteuthis.— Fins — — — ? Shell narrow, gra- 
dually dilated above. 
B. Tentacular Arms with Hooks . Sessile Arms with Cups and 
Rings. 
6. Onychoteuthis. — Club of tentacular arm with hooks. Shell 
lanceolate, pennate, sides thin. 
7. Ancistroteuthis. — Club of tentacular arm with hooks only. 
Shell narrow, rather dilated in front, with one central and 
two marginal ribs. 
8. Onychia. — Club of tentacular arm with hooks on the centre, 
and with two rows of small cups on each side. Shell lanceolate, 
pennate. 
C. Tentacular and sessile Arms with Cups and horny Rings. 
9. Ommastrephes.— Fins rhombic, posterior, caudal. Internal 
cartilage of mantle dilated below. Shell narrow, dilated in 
front with one central and two marginal ribs. 
A. Tentacular and sessile Arms furnished with Hooks. 
1. ENOPLOTEUTHIS. 
Body elongate, with regular longitudinal lines of minute tubercles 
beneath ; sometimes produced into a more or less elongate acute 
tail. Fins angular, on the hinder part of the back; together 
rhombic. ™ Head rather large, subcylindrical. Buccal mem- 
brane eight-lobed ; two upper bands distinct, and inserted 
between the two dorsal arms.— - Sessile arms with a series of 
closed horny claw-like hooks, enlarged at their base, and 
