CEPHALOPODA OF THE HAWAIIAN ISLANDS. 



343 



Individuals of the corresponding stage in the degree of separation of the tentacles approximate 

 very closely to the brief account and figure of R. chuni as given by Hoyle, and may very well be con- 

 generic with it, although only the identification of the adults will show whether they are referable to 

 the same species. The fact that the suckers extend more than half way along the tentacles of the largest 

 specimen affords a certain suggestion that the present series are larval Ommastrepkes hawaiiensis . 



Rhyncoteuthion /?. 



Animal small, pelagic; mantle elongate, less than half as wide as long; nearly cylindrical, slightly 

 tapering, bluntly pointed posteriorly. Fins almost continuous above, minute, rounded, subterminal. 

 Anterior margin of mantle with a faint medio-dorsal angle; very weakly emarginate below the funnel. 

 Locking appartus typically Ommastrephid. 



Head small, flattened; a little wider than the body. Eyes large, rounded; apertures angled in 

 front. Funnel short, broad, not reaching to the eye openings. 



Arms very short, unequal, the ventral pair decidedly the shortest; suckers moderately large, bi- 

 serial, obliquely placed on short pedicels; horny rings minutely toothed. 



Tentacles shorter than the arms, and remarkable in that their inner faces are fused with one another 

 for only a short space below the free recurved tips. When examined with a high-power lens each ten- 

 tacle is seen to be furnished with a number of small suckers just distal to the point of fusion, one of 

 which is greatly larger than the others, hood shaped, distinctly pediceled, its horny ring minutely 

 toothed, median in position, and placed in close opposition to its mate of the other tentacle. 



Color in alcohol a pale brownish buff, the chromatophores considerably darker. There is a pair of 

 large rather conspicuous chromatophores transversely placed on the dorsal aspect of the head. 



Measurements op Rhyncoteuthion /?. 



Total length 12. 5 



Length of mantle, dorsal 8 



Width of mantle 3 



Width of head 3.5 



Length of head 2 



mm. 



Width across fins 3 



Length of fins 1.5 



Length of second arms 2.5 



Length of tentacles 1.5 



lati- 



Material examined. — The single specimen was taken from the surface Albatross station 3930, 

 tude 25 07' N., longitude 170° 50' W., between Honolulu and Laysan Island (S. S. B. 246). 



Remarks. — The unique specimen forming the subject of the foregoing account is a minute squid 

 at once distinguishable from the preceding by its elongate more pointed body and entirely different 

 arrangement of the chromatophores. The curious pair of large opposite suckers on the tentacles may 

 merely represent the first of these structures to become fully differentiated, but their entire aspect is 

 rather that of some temporary larval adaptation. 



Family CHIROTEUTHIDjE Gray 1849. 



Chiroleuthidcz Gray 1S49, p. 36, 42. 

 Ckiroteuthid<B Verrill 1881, p. 430. 

 ChiroteulhidcE Pfeffer 1900, p. 153, 183. 

 ChiroleuLhida Chun 1910, p. 216. 

 ChiroteutkidiE Pfeffer 1912, 539. 



Body soft and semigelatinous or somewhat membranous. Mantle elongate, terminating in an acute 

 and often slender point. Fins large. Head elongate; "olfactory tubercle" stalked. Arms with two 

 rows of suckers, the ventral pair usually conspicuously the longest and largest. Tentacles very long, 

 the stalk without suckers; club with four or more rows of suckers; none of the suckers on either arms or 

 tentacles modified into hooks. Funicular locking cartilages broad, deeply grooved, usually more or 

 less ear-shaped. Gladius slender, with weak narrow wings and a long cone. Photogenic organs may 

 occur over the outer surface of the body, on the eyeball, or within the pallial chamber; frequently 

 absent. 



