CEPHALOPODA OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 95 



(fig. 1) on all the eight arras are enlarged for the second quarter of the arm ; after 

 about the first twelve suckers they enlarge very rapidly for about six suckers, and 

 then gradually diminish. The third arm on the right side is hectocotylised (fig. 2), 

 and is considerably shorter than its fellow on the opposite side. The seminal groove 

 is well marked, but is neither very broad nor very deep ; the modified extremity 



FIG. 3. Radula of Polypus brucei [H 924]. x 25. 



is unusually long and narrow, and, instead of the usual transverse ridges, shows a 

 double row of small papillae along its bottom. 



The Surface shows a considerable amount of wrinkling, due apparently to the 

 action of preservative fluids, but was most probably smooth when the animal was 

 alive. There is no trace of any warts or tubercles. 



The Colour is dull purplish above, changing gradually into a pinkish stone 

 colour below. 



The Radula is shown in fio-. 3. 



Dimensions in Millimetres. 



End of body to mantle margin .... 



End of body to eye 



Breadth of body .... 



Breadth of head ..... 



Eye to edge of umbrella 



Length of hectocotylus ..... 



Breadth of hectocotylus .... 



1 liaiueter of largest sucker on arm 



Length of first arm 

 Length of second arm 

 Length of third arm 

 Length of fourth arm 



Right. 

 270 

 185* 

 200 

 255 



Mutilated. 



58 

 75 

 60 

 50 

 60 

 17 

 3 

 15 



Left. 

 275 

 250* 

 260 

 255 



This species is evidently nearly related to P. megalocyathus (Gould) from the 

 same geographical region. It differs, however, in the absence of the extremely 



(BOY. sou. EDIN. TRANS., VOL. XLVIII., 277.) 



