18 



Anterior antennae considerably more elongated than in female, with the outei 

 part less pronouncedly compressed and the sensory seta much more fully de- 

 veloped, the 2 prolonged apical setae almost attaining the entire length of the 

 shell. Inner ramus of posterior antennae with the middle joint about the length 

 of the 1st and somewhat widening distally, carrying beyond the middle an- 

 teriorly 3 subequal setae, terminal joint forming a somewhat compressed claw 

 impinging upon the preceding joint. Structure of the remaining limbs almosl 

 exactly as in female. Copulative appendage divided at the end into 4 obtusely 

 rounded lobules. . 



Colour in both sexes whitish grey. 



Length of adult female amounting to 2.20 mm, of male to 2.40 mm. 



Remarks. As seen from the above-given list of synonymes, this form 

 has been recorded under several different names. On a closer comparison ] 

 have convinced myself, that the form described by me in 1869 as A norvegica 

 is in reality identical with the British species A. marice (Baird), and that the 

 Mediterranean form A. oblonga (Grube) is the same species. I should alsc 

 be much inclined to believe, that the form recently recorded by Dr. Skogsberg 

 as A. Grimaldi is not specifically distinct from the species here in question, 

 How far the Copechcete elongata of Hesse, as believed by. G. W. Mtiller, i 

 identical with the present species, it is rather difficult to state with full certainty, 

 though I regard the identity by no means as improbable. 



The present species may be easily recognised by the unusually narrow, 

 almost cylindrical shape of the shell in fully adult females. In youngei 

 specimens, however, the shell appears somewhat shorter and stouter, though 

 otherwise agreeing with that in the adults. The male exhibits a much similai 

 appearance to that of other species of the present genus. 



Occurrence. I have only met with this form quite occasionally, though 

 in several places, both on the south and west coasts of Norway. It is gene- 

 rally found in depths ranging from 20 to 60 fathoms, on a muddy bottom, 

 but never in any considerable number. Whereas the females almost constantly 

 keep themselves close to the bottom, the much more agile males in some 

 cases ascend to the very surface of the sea, being occassionally found among 

 plankton taken by the aid of the townet. 



Distribution. West coast of Sweden, British Isles, coast of France, 

 Mediteranean. 



