REPORT ON THE CEPHALOPODA. 



77 



Octopus occidentalis, Steenstrup, MS. 



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

 1853. „ vulgaris, var. americanus, d'Orb., Moll. Cuba, p. 14, tab. i. 



Habitat. — Ascension, April 1876. One specimen $ . 

 Cuba (d'Orb). 



TJie Body is short and oblong, somewhat expanded behind, and deeply grooved in 

 the middle line. The mantle-opening terminates midway between the eyes and the 

 siphon, which is conical, pointed and of quite the average length, extending fully half- 

 way to the umbrella-margin. 



The Head is very short and as broad as the body, the eyes being very prominent 

 and the eyelids much contracted. 



Tlie Arms are subequal, about six times the length of the body. The umbrella 

 extends nearly one-third up the arms, to the least extent apparently between the dorsal 

 pair, though this may be owing to the state of contraction. The suckers are of moderate 

 size, but present no characteristic peculiarities. The circumoral lip is invisible, owing 

 to its retraction, the suckers extending quite to the centre. 



Tlie Surface is rough, slightly so on the body, but with minute irregular papillse 

 scattered over the head and the outer surfaces of the arms. The internal surface of the 

 umbrella bears very numerous papilla;, which are aggregated into clusters, between which 

 the skin is smooth ; they extend over the inner surface of the arms between the suckers, 

 and the wall of these bears minute warts on its outer surface. There are traces of one 

 or two irregular cirri over each eye, but none can be found on the back. 



The Colour of the upper surface of the body, head, and outside of the arms is dark 

 brown, almost black, the ventral surface of the body being amber-brown; the inner 

 surface of the umbrella is pale yellow, the groups of papillae being still of a pinkish hue, 

 though not so deeply coloured as in d'Orbigny's figure {loc. cit.), which was perhaps 

 drawn from lifa 



Dimensions. 

 Length, total, ........ 300 mm. 



End of body to mantle margin, ...... 35 



End of body to eye, 

 Breadtb of body, . 

 Breadth of head, . 



Eye to edge of umbrella, . 

 Diameter of largest sucker. 



Length of first arm. 

 Length of second arm. 

 Length of third arm, 

 Length of fourth arm, 



' Mutilated. 



55 

 50 

 40 

 about 50 

 7 

 Right. 

 235 mm. 

 235 „ 

 230 „ 

 220 „ 

 The lengths of the arms are measured from the margin of the mouth. 



Left. 

 1201 ujjj, 

 240 „ 

 230 „ 

 230 „ 



