THE CEPHALOPODA 



339 



Keferstein. Arms 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 



Fio. 298. 



Decapod Cephalopoda. A, Cheiroteuthis Veranyi, dorsal aspect; B, Thysanote-uthis rhombus, 

 dorsal aspect ; C, Leachia q/clura, 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. Lepidoteiithis, 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 



