CEPHALOPODA OF THE HAWAIIAN ISLANDS. 273 



10'. Photophores not conspicuously differentiated into two main types; their 

 bilateral arrangement obscure; fins half -as long as the mantle. 



Abralia trigonura, p. 329. 

 9'. Buccal membrane dark reddish or violet in color; ventral arms with a series of 

 three conspicuous heavily pigmented beadlike organs at their tips. 



Abraliopsis sp., p. 331. 

 8'. Tentacle club with suckers only, but few hooks on sessile arms; numerous photo- 

 genic organs on the eyeball and within the pallial cavity, but none on the outer 



aspect of the mantle Pterygioteuthis microlampas, p. 332. 



5'. None of the suckers with their chitinous rings transformed to hooks. 



11. Mantle free all round anteriorly (not true of Symplecloleutkis , as see below). 

 12. Numerous photogenic organs on the body, head, and arms. (Family 



Histioteuthidae), p. 335. 

 12'. Photogenic organs few in number or absent. 

 13. Funnel articulating with the mantle by a j_-shaped groove. (Family 

 Ommastrephidse.) 

 14. Sucker bearing portion of tentacles greater than half the total length; 

 fixing apparatus poorly developed. Ommastrephes hawaiiensis , p. 338. 

 14'. Sucker bearing portion of tentacles less than half the total length. 

 15. Mantle fused with the funnel on at least one side; fixing apparatus 

 a distinct carpal group of pads and suckers. 



SympUctoteuthis oualaniensis , p. 341. 

 15'. Animal small; clubs of tentacles fused to form an X-shaped or 



proboscis-like organ " Rhyncoteuthion" , p. 341. 



13'. Funnel articulating with the mantle by a simple pit or groove. 



16. Mantle delicate, membranous, transparent; fins sagittate; 



pelagic Brachioteuthis riisii, p. 336. 



16'. Mantle fleshy, produced to a delicate point posteriorly; fins 

 lanceolate, over half as long as the mantle ; ventral arms much 



thelongest Mastigolcuthis ( })famelica, p. 344. 



1 1'. Mantle fused with the funnel on either side and with the head in the nuchal 

 region; mantle ample, thin, transparent; viscera confined to a very 

 small proportion of the pallial cavity. (Family Cranchiidsei. 



17. Mantle ornamented with several series of cartilaginous tuber- 

 cles; mantle greatly inflated. .Liocranchia globulus, p. 346. 

 17'. Mantle smooth; only moderately inflated. 



18. Eyes enormous, rounded , sessile . Megalocranchiafisheri, p . 348. 

 iS'. Eyes much smaller, oval, upon short stalks. 



H elicocranchia sp., p. 350. 



Note. — Except in the case of one or two well-known and widely distributed species, it has been my endeavor in the follow- 

 ing pages to make the list of references preceding the description of each species as*nearly complete as possible, and it is hoped 

 that the occasional parenthesized comments regarding the nature of particular citations will prevent the confusion which might 

 otherwise accrue through the promiscuous cataloguing of trivial and important references in the ssmc tables. An attempt has 

 been made to economize the time of the reader by printing all citations of special present importance in bolder type than the 

 remainder. 



Phylum MOLIUSCA. 

 Class CEPHALOPODA Cuvier 1798. 



Octopodia Schneider 1784, p. 108. 



Cephalopoda Cuvier 1798 (fide Gray). 



Cephalopodia Rafinesque 1815, p. 139 {fide Binney and Tryon, p. 14). 



Cephalophora de Blainville 1825, p. 364. 



