1062 CEPHALOPODA. [Dibranckia. 



2. Sepioteuthis Lessoniana, Ferussac, 1826. Plate 70, figs. 2, a. 

 Sepioteuthis Lessoniana, d'Orbigny, Tab. Meth. Ann. de Sci. Nat., vii, 1820, 

 155: Lesson, Voy. Coq., ii, 1830, 244, pi. 2: d'Orb., Ceph. acet,, 302, 

 Sepioteuth.es, pi. 1, 6, f. 9-14 : Gray, Ceph. Antep. Brit. Mus., 1849, 

 80 : Man. Conch. (1), i, 152, pi. 62, f. 212 ; pi. 64, f. 213 : C.M.M., 3 : 

 M.N.Z.M., 3 : Appelof, Japanska Ceph., 1886, 31 : Chall. Rep., xvi, 

 27, 151 : Index, 58 : Brazier, Cat. A.M., No. 15, 14. 



Body elongate, spotted with violet ; fins dilated posteriorly ; sessile 

 arms elongate, cups oblique, rings with, distant acute teeth ; tenta- 

 cular arms bluntly clubbed, cups large, very oblique, rings with distant 

 acute curved teeth ; buccal membrane with cups. Shell lanceolate, 

 broadest in the middle, outer edge not thickened, central rib broad, 

 extended in front, one-fifth of the length. (Gray.) 



Dimensions of a Specimen from Ternate. Length, total, 570 mm. : 

 end of body to mantle-margin, 195 mm. : breadth of body, 85 mm. : 

 breadth of fin, 45 mm. : length of first arm -right, 70 mm. ; left. 

 66 mm. : length of fourth arm right, 95 mm. ; left, 100 mm. : length 

 of tentacle right, 320 mm. ; left, 335 mm. 



Type in the Mus. Hist. Nat., Paris. 



Hob. Bay of Islands (Antarctic Expedition). Fiji, Ternate (Chal- 

 lenger Expedition) ; New Guinea ; Java ; Cape Favre ; Trinco- 

 malee ; Japan. 



SUBORDER 2. OCTOPODA. ' 



These Dibranchia have only 8 arms, which are all similar and 

 longer than the body. The body is short and rounded aborally. 

 The suckers are sessile. The heart is not contained in the coelom. 

 There are no nidamentary glands. The Octopoda comprise two tribes, 

 the Leioglossa and the Trachyglossa. 



Tribe 2. TRACHYGLOSSA. 



These are Octopoda with a radula and without true fins. 



Fam. POLYPODID^!, Hoyle. 



OctopodidcK. 



Arms long and equal, without a true interbrachial membrane, 

 subulate, elongated. Mantle supported by fleshy bands. No cephalic 

 aquiferous pores. The hectocotylus is not caducous. Formula of 

 radula 3.1.3. 



Genus 1. POLYPUS. Schneider, 1784. 



rlypus, J. G. Schneider, Samml. verm. Abhandl., 1784, 116. Type: 

 Octopus vulgaris, Lamarck. Octopus, Lamarck, 1798. 



Body oblong-rounded, without fins ; arms long, unequal, the 

 suckers sessile, in 2 rows on each arm. Third right arm of male hecto- 

 cotylized. 



About fifty species, inhabiting all seas. These animals live mostly 

 hidden in rock-fissures ; they are extremely voracious, and feed on 

 bivalves and larger crustaceans. 



