Boone, Mollusca, Cruises of "Eagle" and Ara," 1921-28 165 



MOLLUSCA: SYSTEMATIC DISCUSSION 



CEPHALOPODA. 



Order: DIBRANCHIATA. 



Suborder: Decapoda. 



Family: ONYCHOTEUTHIDAE. 



Subfamily : Onychoteuthinae. 



Genus: ONYCHOTEUTHIS Lichenstein. 



Onychoteuthis banksii (Leach). 



Plate 104. 



Type : Leach 's type was deposited in the British Museum. The type 

 locality was not cited in the original description, which is in a synopsis 

 of Cephalopoda. In 1818 this species is described a little more fully 

 and referred to as a new species from the Gulf of Guinea. 



Distribution: Practically cosmopolitan. This sea-arrow has been 

 taken in all the oceans at numerous stations. It seems equally at home 

 in Arctic or tropic seas. It is known from the Arctic to the Cape of 

 Good Hope and Indian Ocean and also throughout the Atlantic and 

 Pacific Oceans. 



Material examined: Two very young specimens from Bimini, 

 British "West Indies, January 19, 1923. One young specimen, taken 

 seventeen miles S. W. of Pinta Island, Galapagos, January 31, 1928. 

 One specimen about six inches long, washed up on the upper deck 

 of the "Ara" between Madeira and Casa Blanca, Morocco, August 

 4, 1924. One, slightly larger, that "flew" twenty feet above sea level, 

 coming over the bow of the "Ara" and landing on the bridge, during 

 a cruise between Madeira and Casa Blanca, Morocco, August 19, 1924. 



Color : See Tryon 's color plate, which shows this squid to be wine 

 red with darker chromatophores and bluish circles about the eyes. 

 Leach described the living specimens as "pale flesh color, the body 

 yellowish posteriorly sprinkled irregularly with blackish spots tinted 

 with purple." 



Technical description : Consult Pf effer, 1912, for a very thorough 

 anatomic description. The average body length is six inches. The 

 present specimen is 105 mm. long, subcylindrical anteriorly, decidedly 

 tapered posteriorly, cone-like; anterior mantle margin produced to a 

 median dorsal angle; ventral margin shallowly excavate beneath the 

 siphon. Fins rhomboidal, not quite half the body length; width 

 across from tip to tip equal to three-fourths of body length, or about 

 one and one-half times the length of the fins; there is a slight angle 

 at the anterior insertion of the fins ; their lateral and posterior angles 



