REPORT ON THE CEPHALOPODA. 



97 



Octopus januarii, Steenstrup, MS. (PI. VII. figs. 1-4). 



Octopus januarii, Steenstrup, MS. in Mus. Havn. 

 1885. „ „ Hoyle, Diagnoses L, p. 229. 



1885. „ ,, Hoyle, Prelim. Rep., p. 105. 



Habitat. — Station 122, off Barra Grande, Brazil, September 10, 1873; lat. 9° 5' S., 

 long. 34° 50' W.; 350 fathoms; red mud. One specimen, $ . 



Station 237, North Pacific, east of Japan, June 17, 1875; lat. 34° 37' N., long. 

 140° 32' E.; 1875 fathoms; blue mud. One specimen, ^ . 



Rio Janeiro (Copenhagen Museum). 



The Body is rounded, widening a little posteriorly ; the ventral groove is very faint. 

 The mantle-opening terminates just below the eyes. The siphon is bluntly conical, and 

 extensively attached to the umbrella ; it extends less than halfway to the umbrella margin. 



The Head is small, and tlie sides are entirely occupied by the enormous eyes, which 

 are swollen and globular, but with very small palpebral openings. The skin covering 

 them is so thin that the dark pigment within is distinctly visible. 



Tlie Arms are unequal, the dorsal pair being the largest ; on an average they are six 

 times as long as the body. ' The umbrella is about equally wide all round, except that it 

 is a little shorter between the two ventral arms. 



The Suckers are comparatively small, prominent, and separate ; more widely in one 

 specimen than in the other, probably owing to its being less contracted by spirit. None 

 of the suckers on the lateral arms are enlarged, notwithstanding the sex. The extremity 

 of the hectocotylised arm is well developed ; it is broad, and tapers rapidly to an acute 

 point ; in one specimen about seven transverse ridges can be counted iii the proximal 

 half of the median groove ; in the distal half and in the other specimen they are indistinct 

 (PL VII. fig. 2). 



TJie Surface is perfectly smooth all over. 



The Colour is a pale purplish-pink ; deeper above than below. 



T7ie Jaivs are shown in PI. VII. figs. 3, 4. 



Dimensions 



1 









Length, total, .... 



285 mm 



End of body to mantle margin, 











35 „ 



End of body to eye, 











47 „ 



Breadth of body, ... 











42 „ 



Breadth of head, . 











32 „ 



Eye to edge of umbrella, . 











58 „ 



Length of tip of hectocotylised arm, 











10 „ 



Breadth of tip of hectocotylised arm, 











4 „ 



Diameter of largest sucker, 







L .1, 



4.; — +!,«, 



3-5 „ 



1 The measurements are from the Barra Grande specimen ; it was in better condition than the other, which had also 

 a length of about 290 mm. The lengths of the arms are measured from the eye. 



(ZOOL, CHALL. EXP. — PART XLIV. 1886.) Xx 13 



