260 Th. Mortensen. 



ously Mi chailovskij found the two same types and distinguished 

 them as forma lœvior, the typical form, and forma scabrior, that 

 with the single spines. Until a careful revision of the species has 

 been undertaken, I think it right to distinguish these two forms. — 

 Probably the forma scabrior Avill prove to be a special cold-water 

 form, as Solaster glacialis and S. papposiis, var. squamatus; but the 

 fact that the forma lœvior occurs together with f. scabrior in the 

 cold region makes the case more intricate. 



The specimen from Stat. 72 has a very extraordinary appearance 

 and at the first aspect does not appear to belong to this species. 

 The difference is, however, only occasioned by the skin covering 

 the spines being very thick and swollen; otherwise the specimen 

 agrees completely with the forma scabrior. The spines are not 

 united by weblike expansions of the skin. 



8. Pteraster militaris (O. Fr. Müller). 

 PL XVI. Fig. 2. PI. XVII. Figs. 1, 11. 



Pteraster militaris Düben & Koren. 1844. üfvers. Skand. Ech. 

 p. 246. Tab. VII. Figs. 11— 13. 



— — Lût к en. 1857. Grønlands Echinod. p. 43. 



— — Sars. 1861. Norges Echinod. p. 48. Tab. III. 



Figs. 8— 9. Tab. IV— VI. 



— — Duncan & Sladen. 1881. Mem. Echinod. Arctic 



Sea. p. 46. PI. III. Figs. 13—16. 



— — Danielssen & Koren. 1884. Norske Nordh. Exp. 



Asteroidea. p. 70. PI. XIII. Figs. 18-19. 



— — Ludwig. 1900. Arktische Seesterne. Fauna Arc- 



tica. p. 469. 



— — Grieg. 1902. Overs, nordlige Norges Echinoder- 



mer. p. 27. 



— — Th. Mortensen. 1903. Echinoderms from East 



Greenland, p. 77. PI. II. Figs. 4—5. 



— — Süssbach u. Breckner. 1910. Seeigel, Seesterne 



u. Schlangensterne d. Nord- u. Ostsee, p. 226. 



Station 63. Stormbugt, 10—20 m. 1 specimen, poorly preserved. 



I have been unable to find in the dorsal skin of this specimen 

 any of the calcareous corpuscles otherwise so characteristic of this 

 species. — The figures given by Sars of these corpuscles do not 

 appear to me very satisfactory, so I have taken the occasion to give 

 a few, more detailed figures of them from some other Greenlandic 

 specimens (PI. XVII. Figs. 1,11). 



The paxillæ of this specimen bear 4 spinelets. 



