CEPHALOPODA OF THE HAWAIIAN ISLANDS. 273 
lo'. Photophores not conspicuously difierentiated into two main types; their 
bilateral arrangement obscure; fins half -as long as the mantle. 
Ahralia 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. 
II. Mantle free all round anteriorly (not true of Syniplectoteutkis, 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 jL-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 fimnel on at least one side; fixing apparatus 
a distinct carpal group of pads and suckers. 
‘ Sympleclotenihis 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 riisei, p. 336. 
16'. Mantle fleshy, produced to a delicate point posteriorly; fins 
lanceolate, over half as long as the mantle; ventral arms much 
thelongest Mastigoteuthis (?) 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 Cranchiidae). 
17. Mantle ornamented with several series of cartilaginous tuber- 
cles; mantle greatly inflated. .Lfocrawc/z fa globulus, p. 346. 
17'. Mantle smooth; only moderately inflated. 
18. Eyes enormous, rounded, sessile .Megalocranchiafisheri , p. 348. 
18^. Eyes much smaller, oval, upon short stalks. 
Helicocranchia sp., p. 350. 
Notb. — 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 i>arenthesized 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 same 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 MOLLUSCA. 
Class CEPHALOPODA Cuvier 1798. 
Ociopodia 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. 
