CEPHALOPODA OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 277 
(fig. 1) on all the eight arms 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 
Fic. 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 papillee 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 fig. 3. 
Dimensions in Millimetres. 
End of body to mantle margin . : : : 58 
End of body to eye : : : - : 75 
Breadth of body ; : : : , 60 
Breadth of head : ; : ; : : 50 
Eye to edge of umbrella : ; : 60 
Length of hectocotylus . , ; : . 17 
Breadth of hectocotylus ; : : ; 3 
Diameter of largest sucker on arm : : : 15 
: Right. Left. 
Length of first arm : ; : : : 270 275 
Length of second arm__.. ‘ , 185* 250* 
Length of thirdarm ; : ; 200 260 
Length of fourth arm . : ; : 255 255 
* Mutilated. 
This species is evidently nearly related to P. megalocyathus (Gould) from the 
same geographical region. It differs, however, in the absence of the extremely 
