610 MOLLUSCA 



trunk; shell (pen) lanceolate, narrow; length 20 em.; width 6 cm.; 

 color dark grayish with reddish spots; eggs deposited in long cylindrical 

 jelly masses, attached together at one end: Maine to South Carolina; 

 very common. 



L. pallida Verrill. Very similar to above; body thick, fins more 

 than half the length of the trunk; color pale with few spots; length of 

 body 20 cm. ; length of fin 75 mm. : Long Island Sound. 



Family 3. OMMASTREPHIDAE. 



Body cylindrical, elongate; fins terminal, joined together and rhom- 

 bic; arms usually short, with varying number of rows of suckers; eyes 

 naked, without a cornea; siphons united by bands to the head; pen slen- 

 der and small, with a hollow cone at the hinder end : cosmopolitan ; about 

 25 species, mostly in the open ocean. 



Key to the genera of OmmastrepJiidae here described: 



Oi Size small or moderate 1. Ommastrephes 



Cj Size very large 2. ARcniTEUTiiis 



1. Ommastrephes D'Orbigny. Sea arrows. Flying squids. Body 

 elongate; arms with 2 rows of suckers; tentacular arms not retractile 

 and wdth 4 rows of suckers; siphon valved: 13 species, 4 American. 



0. illecebrosus (Lesueur) (Fig. 959). Fins about half as long as the 

 trunk; length 30 cm.; width 3 cm.; length of fin 8 cm.; length of sessile 

 arms 10 cm.; of tentacular arms 18 cm.; color deep blue, passing into 

 red, spotted, sometimes pale: eastern end of Long Island Sound to Bay 

 of Fundy and northwards, common north of Cape Cod; very swift in 

 motion. 



O. bartrami (Lesueur). More slender, elongated, and darker-colored 

 than the above, with a relatively shorter caudal fin: Gulf stream, some- 

 times off the coast. 



0. tryoni Gabb. Length 20 cm. : very common on the coast of Cali- 

 fornia, where they are caught in great numbers by Chinese fishermen 

 and dried for exportation to China. 



2. Aechiteuthis* Steenstrup. Giant squids. Differs from the pre- 

 ceding genus in that an irregular group of small, smooth-rimmed suckers 

 are on each tentacular arm, intermingled with rounded tubercles; suck- 

 ers of sessile arms strongly denticulate; fins shaped like an arrowhead: 

 9 species, in the deep sea in all parts of the world, most of the specimens 

 accurately kno\\Ti having been captured in the North Atlantic. 



♦ See "The Colossal Cephalopods of the North Atlantic," by A. E. Verrill, Am. 

 Nat., Vol. 9, p. 21, 1875. 



