EEPORT ON THE CEPHALOPODA. 



99 



groove runs across the arm between each two suckers (possibly due to contraction). 

 The extremity of the hectocotylised arm is well- developed, short, and tapering rapidly 

 to. a blunt point; the median groove has about ten transverse bars (PI. I. fig. 2). 

 The circumoral lip is unusually thick (PL III. fig. 1). 



The Surface appears to have been perfectly smooth,^ but is now covered with 

 wrinkles, due to the action of the spirit. 



The Colour is a dull grey, inclining to stone-colour below. 



Tlie Jaivs are shown in PL IL figs. 3, 4. 



190 mm. 

 43 

 50 

 40 

 35 

 50 



7 



4 



3 



Right. 



Left. 



125 mm. 



140 mm 



130 „ 



140 „ 



100 „ 



130 „ 



135 „ 



130 „ 



Dimensions. 



Length, total. 



End of hody to mantle margin, 



End of body to eye. 



Breadth of body, . 



Breadth of head, . 



Eye to edge of umbrella, . 



Length of extremity of hectocotylised arm, 



Breadth of extremity of hectocotylised arm 



Diameter of largest sucker, 



Length of first arm,^ .... 



Length of second arm, .... 



Length of third arm, . . 



Length of fourth arm, . . . . 



The establishment of this species is more than usually satisfactory, being based 

 upon no less than four specimens ; and although three of these were of small size, yet 

 they agree so well with the large one that there would be no doubt as to their identity 

 even had they not been obtained at the same Station. 



In some respects, for instance, in the absence of cirri, and in its smooth skin, it 

 resembles Octopus tehuelchus, d'Orbigny, but the specimens differ from the latter so 

 very markedly in colour (d'Orbigny's form being of a deep blackish-brown), and in some 

 minor points, that there is no doubt they are distinct. 



In its smoothness and in the form and dimensions of the extremity of its 

 hectocotylised arm it also resembles Octopus januarii, Steenstrup, but it is certainly 

 distinct. From Octop)Us favonia. Gray, it difl"ers in the presence of a stout circumoral 

 lip, and in the double row of cups reaching quite up to it (PL III. fig. 1) ; the latter 

 is in most cases a comparatively insignificant character, but seems to be of more value in 

 the present instance because the arms were strongly bent back from the mouth, a con- 

 dition in which the suckers would naturally tend to form a single series. 



' Hence the specific name. 



2 The lengths of the arms are measured from the marghi of the mouth. 



