268 



BIOLOGY OF THE SEAS OF THE U.S.S.R. 



Onisimus genus and also Haploops laevis, Ampelisca birulai, Priscillina 

 armata, Acanthostepheia malmgreni; isopods: Mesidothea sibirica, M. sabini 

 robusta ; decapods : Spirontocaris phippsti, Antinoella badia, Castalia aphro- 

 ditoides, Lumbriconereis algida, A. beringiensis, Arrhis phylonyx, Rozinante 

 fragilis, Sabinea septemcarinata, Eualus gaimardi belhcheri; echinoderms: 

 Urasterias linki, Heliometria glacialis, Ophiocten sericeum, Eupirgus scaber ; 

 molluscs : Portlandia arctica, Montacuta spitzbergensis, Periploma fragilis and 

 others. 

 In the southwestern part of the Chukotsk Sea the boreal Pacific Ocean 



Fig. 113. Distribution of (7) high Arctic and (2) boreal 

 Pacific forms in Chukotsk Sea ; (J) Station with both 

 groups ; (4) Stations with low Arctic fauna (Ushakov). 



forms are widely distributed ; 50 per cent of the species consist of these groups 

 of fauna, especially of the Decapoda, Echinodermata and Tunicata. Among 

 the hydroids the following should be mentioned : Halecium ochotense, Abieti- 

 naria variabilis, A. turgida, Sertularia similis; among the polychaetes: Eunoe 

 spinicirrus, E. barbata, E. depressa, Gattyana ciliata, Spinier vegae; among 

 the bryozoans: Eucratea loricata var. macrostoma, Dondrobeania pseudo- 

 levenseni, Leischara orientalis ; among the Cirripedia : Balanus hesperius, Meso- 

 stylis dalli, M. bidentata ; among the amphipods : Ampelisca derjugini, Har- 

 pinia gurjanovae, Pontharpinia nasuta, Metopa submajuscula, M. robusta; 

 the isopod Janiria alascensis; the decapods: Pandalus goniurus, Eualus 

 suckleyi, E. flexa, E. camtchatica, Crangon dalli, Pagurus rathbuni, Para- 

 lithodes platypus, My as coarctatus alutaceus, Chionoecetes opilio ; the molluscs : 

 Yoldia scissurata, Venericardia crebricostata, V. crassidens, V. paucicostata, 



