372 K. STEPHENSEN. 
To the same group belong 6 Echinodermata, viz: 
Phyllophorus pellucidus (extending southwards as far as England) 
Pteraster pulvillus (to southern Norway) 
Solaster papposus (southward as far as the Channel) 
—  endeca (southward as far as Ireland, but not found N. of Siberia) 
Ophiacantha bidentata (also found in the deep Atlantic, and Japan) 
Strongylocentrotus droebachensis (southward as far as the Channel). 
These are found in the “Rink” material with the exception of Pte- 
raster pulvillus and Solaster endeca. 
Both Crustacea and Echinodermata belonging to this group are 
thus represented in the “Rink” material by about the same high per- 
centage, viz: abt. 6”— 70 °/). 
4. Species of uncertain zoogeographical position. 
(К. St., Danmark Exped. р. 615; Conspectus р. 421). 
Under this head should be classed at least 16 (15) Crustacea and 
Pycnogonida, and among Echinodermata, Ophioscolex glacialis, which 
however, belongs rather to the deep Atlantic, but is also found in the 
arctic deep. Only the lastnamed is found in the “Rink’ material. 
The fact that it is not at present possible to refer all the Green- 
land species to definite zoogeographical groups would seem to be due, 
not only to incomplete knowledge of the species in question, but also 
to the fact that some species are not particularly sensitive as regards 
temperature, and may thus be found outside the area of their principal 
occurrence. APPELLOF has, in “Havbundens Dyreliv, (Norsk Havfiske; 
Norges Fiskerier, 1. 1905, p. 72, 73, 101, and also in Murray and Hjort; 
The Depths of the Ocean 1912, p. 533) mentioned a number of transition 
forms. J. GRIEG also, in “Evertebratfaunaen paa Havdypet utenfor 
"Tampen’ — Bergens Museums Aarbok 1914, No. 3, р. 4 seq.) men- 
tions forms properly belonging to the high arctic regions, but which 
also penetrate into the boreal areas. Among Greenland Echinodermata 
Grieg thus notes Ophiopleura borealis, Ophiopus arcticus, Gorgonoce- 
phalus eucnemis, Tylaster Willei, Poraniomorpha tumida, Solaster squa- 
matus, Korethraster hispidus and Hymenaster pellucidus. 
5. Species found both in the Atlantic and the Pacific (“ American” species). 
(К. St., Danmark Exped. р. 617; Conspectus р. 422.) 
Of Crustacea and Pycnogonida this group includes, besides the 
25 species named in the Danmark Exped. and the Conspectus, also 
Eupagurus pubescens. 
Of Echinodermata, we have here: 
Chirodota laevis Laetmogone violacea 
?Eupyrgus scaber Cucumaria calcigera 
Molpadia oölitica Leptychaster arcticus 
