Cephalopoda of the Trondhjem Region. 



1. OCTOPODA. 



Polypiis arcliciis Prosch, 1847. 



Octopiis arcticus Steexstrup, 1857. 



— Bainlii G O. Sars, 1878. 



— — Verrill, 1881. 



-77 1911. Skamsund, ca. 200 m., coral boltom, 1 specimen. 



Vs 1916. Off Tommerdal in Leksvik, 100—200 m., clay boltom, 1 



specimen, 3. right arm hectocotvlized. 

 -78 1920. N. of Taulra, 100—200 m., clay bottom, 3 specimens. 

 79 1920. Lensvik, 100—300 m., coral and clay bottom, 1 specimen, 

 3. right arm hectocotylized, length from end of body to 

 mantle-margin, 20 mm. 

 "77 1913. Galgenes, ca. 100 m., rocky bottom, 1 specimen, 3. right 

 arm hectocotylized, length from end of body to mantle- 

 margin, 25 mm. 

 ^78 1910. Garten, ca. 250 m., clay bottom, 3. right arm hectocoty- 

 lized, length from end of body to mantle-margin, 34 mm. 

 Thus this species has been observed at several localities in the 

 Trondhjem Fjord. In V. Storm's collection I have seen 7 speci- 

 mens from the same fjord, localities not recorded. A male caughl 

 in July 1896 had the 3rd right arm hectocotylized. A yoimg, or at 

 least a very small specimen, I tok 'V« 1920 off Tonnel in the outer 

 part of the fjord. Length from the end of body to mantle-margin 

 was only 5 mm. 



Distribution. — Greenland (Posselt and Jensen, 1898, 

 p. 270); Newfoundland to South Carolina (Verrill, 1881, p. 370); 

 West-Spitsbergen (Knipowitch, 1901, p. 104); Between Bear-Is- 

 land and Norway, 72°27' N., 20°51' E. (Appellof 1892, p. 3); Nor- 

 wegian coast from Vadso to Kvitingso (G. O. Sars, 1878, p. 340); 

 Skagerack and Bohuslen (Lonnberg, 1891, p. 7); Færo Channel 

 (HoYLE, 1886, p. 91); Irish coasts (Massy, 1909, p. 6). 



The occurence at a station off West Spitsbergen is very interest- 

 ing. This faet indicates that this boreal species which has been 

 named arcticus is moving to the arctic regions by aid of the north- 

 going warm current. 



