THE CEPHALOPODA 



339 



Keferstein. Anns enlarged, bearing two rows of suckers and filaments. 

 Fins triangular, extending along the whole length of the body. Genus 

 Thysanoteuthis, Troschel (Fig. 298, B) ; Mediterranean. FAMILY 8. ONYCHO- 

 TEUTHIDAE, Gray. Fins terminal. Tentacular arms long ; the suckers 

 provided with hooks. Genera Onychoteuthis, Lichtenstein ; the hook- 

 bearing suckers exist only on the well-developed tentacular arms. Enoplo- 

 teuthis, d'Orbigny ; tentacular arms well developed ; hook-bearing suckers 



PIG. 298. 



Decapod Cephalopoda. A, Cheiroteiithis Veranyi, dorsal aspect; B, Thysanoteuthis rhombus, 

 dorsal aspect ; C, Leachia cyclura, ventral aspect. (From Lankester, after Verany, Troschel, 

 Ferussac, and d'Orbigny.) 



on all the arms. Veranya, Krohn ; body very short ; fins obtuse ; 

 tentacular arms atrophied in the adult ; Mediterranean. Chaunoteuthis, 

 Appellof ; body elongated ; fins prominent and pointed ; tentacular 

 arms atrophied. Pterygioteuthis, Fischer. Ancistroteuthis, Gray. Abralia, 

 Gray. Teleoteuthis, Verrill. Lepidoteuihis, Joubin. FAMILY 9. GONA- 

 TIDAE, Hoyle. Body elongated ; fins terminal. Radula with only two 

 lateral teeth. Genus Gonatus, Gray. FAMILY 10. CHEIROTEUTHIDAE, 

 Gray. Tentacular arms long and not retractile. Body elongated fins 

 large and rounded. Resisting apparatus well developed. Genera 



