REPORT ON THE CEPHALOPODA. 145 



apparent, and consequently described them as ." seeming " to be in four series. The shell 

 of the Challenger specimen is decidedly narrower than the one figured by Appellof, and 

 the raised median tract appears to be by no means so prominent. 



Metasepia, subgen. nov. 



Body short, rounded, thick dorso-ventrally ; nuchal cartilage without linear groove 

 and mantle devoid of corresponding ridge ; sipliono-pallial articulation deep. 



Tentacular club with unequal suckers. 



Shell rhomboidal in outline, with no calcareous covering on the dorsal surface of the 

 chitinous sheet ; no spine. 



Sepia (Metasepia) pfefferi} Hoyle (PI. XXI. figs. 1-10). 



1885. Sejiia {Metasepia) Pfefferi, Hoyle, Diagnoses II., p. 199. 

 1885. „ „ „ Hoyle, Prelim. Eep. II., p. 304. 



Habitat. — Station 188, south of Papua, in the Arafura Sea, September 10, 1874; 

 lat. 9° 59' S., long. 139° 42' E.; 28 fathoms ; green mud. One specimen, $ . 



The Body is short and stout, broadest about the middle of its length, very thick 

 (dorso-ventrally), and bluntly rounded behind. Th&Jins are one-fourth as broad as the 

 body and placed much nearer the dorsal than the ventral surface ; they commence 2 to 

 3 mm. from the anterior margin and are connected by a narrow fillet behind ; a slightly 

 raised ridge passes down the ventro-lateral aspect of the body. The mantle-margin 

 projects very slightly dorsally and is a trifle emarginate opposite the funnel ; the 

 nuchal cartilage has no distinct linear groove as in most species, but only a sKght 

 depression, while the corresponding part of the mantle has a triangular eminence about 

 half as broad as long, and with the rounded apex directed forwards ; the connective 

 cartilages are deeper than in most species of Sepia, but there is no distinct knob as 

 in Sepiella, their greatest depth being in the middle not anteriorly ; there is no posterior 

 gland. The siphon reaches up to the depression between the ventral arms. 



The Head is broad, and the eyes prominent. 



The Arms are subequal, in order of length 3, 4, 2, 1, or 4, 3, 2, 1 ; they are rather 

 more than half as loug as the body and distinctly three-sided, having a ridge on the 

 outer side of each, broadest on the ventral ones ; they taper evenly to very fine points ; 

 the inner surface of each is roughly papillate, and has hemispherical depressions into 

 which the suckers are retracted. The suckers are in four series throughout, almost 

 hemispherical, not very oblique, and marked with meridional grooves ; the horny ring 

 bears irregular square teeth. The hectocotylus is not developed, the specimen beiug a 



1 Named after my friend Dr. Georg Pfeffer of the Hamburg Museum, who has recently published a valuable 

 catalogue of the Cephalopoda of that institution. 



(ZOOL. CHALL. EXP. — PART XLIV. — 1886.) Xx 19 



