375 



SYSTEMATIC 



Order OCTOPODA, Leach 



Sub-order CIRROMORPHA, Robson, 1929 



Cirroteuthis glacialis, n.sp. 



St. 182. 14. iii. 27. Schollaert Channel, Palmer Archipelago. 

 500 m., mud. Large otter trawl: one (J. 



Dimensions [in mm.). 



Eyes — mantle apex ... ... ... ... 78 Web 



„ — edge of web (between dorsal arms) 

 Interocular width 

 Body, maximum width 

 Fins, length 



64° 21' 00" S, 62° 58' 00" W. 278- 



width . . . 

 Arm (left), length: 

 1st 

 2nd 



3rd ... 

 4th 



140 

 80 

 58 

 75 

 54 



200 



195 



185 



175 



The general appearance is characterised by the extraordinarily deep and heavy fins and 

 the relatively short body and wide head. It is really unlike that of any known species, 

 though in general outline it recalls C. megaptera, Verrill (Joubin, 1920)^. The arms are in 

 the order i, 2, 3, 4. The longest bear about seventy-four suckers. The first fourteen to 

 seventeen suckers are very deeply sunk in the surface tissues. When sectioned they are 

 found to be very muscular, the inferior chamber and suctorial surface being excep- 

 tionally well developed. This fact, considered in relation to the feebleness of the suckers 

 of some deep-water Octopods, renders the problem of the adaptation of these animals 

 extremely baffling {v. anon). 



The cirrhi are disposed as usual. They do not exceed about 5-5 mm. in length, and the 

 proximal and distal ones become very minute. The web is of the pattern A, B, C, D, E. 

 E is well under half the depth of A, a remarkable feature. The head is large, and wider 

 than long. The eyes are ^ of the area of the mantle, and are thus of relatively moderate 

 size (Robson, 1926, p. 1349). The fins are very large. Unlike such forms as C. magna and 

 megaptera- , in which the fins are also very large, the base is nearly the widest part and 

 is not narrow, as in those species. The striking thing about the fins is their very great 

 depth, which is over f of the length from the eyes to the apex of the body. The surface 

 tissues are, as usual, gelatinous, but the general consistency is firmer and more solid 

 than usual. The head and arms and the dorsal surface of the mantle are of a fine bluish 

 purple. The fins and under-surface of the body are more of a reddish tint. A very 



' It is not at all like the original specimen of megaptera (Verrill, 1885, pi. xliii, fig. i). It resembles a 

 specimen taken in 16° 12' N, 24° 43' W and named megaptera by Joubin {loc. cit.). Very unfortunately 

 Joubin did not describe this example in detail and I am quite unable to say if it is rightly named. Though 

 it resembles this specimen in general proportion, the 'Discovery' example differs from it in the size and 

 shape of its fins. 



^ In Joubin's megaptera {loc. cit.) the sides of the fins seem to be parallel. 



