Report on the Echinoderms of North-East Greenland. 



257 



probable that this species has not pelagic larvæ; evidently the eggs 

 must be laid at different epochs, since they do not become ripe at 

 the same time, as is generally the case in those forms, where the 

 eggs develop into pelagic larvæ. 



The present specimen differs not inconsiderably from the typical 

 form in the marginal plates being somewhat spinous and not so 

 regular in shape (PI. XIV, Fig. 4, to compare with PI. XIV, Fig. 6, 

 representing the corresponding plates from a specimen of the typical 

 form). The limit between the upper and lower marginal plates is 

 indistinct, on account of a thick covering skin. Whether this 

 specimen represents a distinct variety or perhaps an individual 

 abnormality can, of course, not be settled on the evidence of the 

 present material. But I am inclined to regard it as an abnormal 

 specimen. In a specimen from the Kara Sea I have found traces 

 of a similar irregularity in the marginal plates, but much less devel- 

 oped than in the present specimen. — Otherwise it agrees with 

 Kalischewskijs cold-water variety. 



Concerning the most interesting geographical distribution of this 

 species, see below, p. 294. 



Solaster iumida 



Asterina — 



6. Porauiomorpha tumida (Stuxberg). 



PI XVI, Figs. 6-7. 

 Stuxberg. 1878. Echinodermer från Novaja 

 Semljas haf, samlade under Nordenskjöldska Ex- 

 peditionerna 1875-1876. Öfvers. Vet. Selsk. For- 

 handl. 1878. p. 31. PI. VI. 



Daniel s sen & Kor en. 1884. Norske Nordhavs 

 Exp. Asteroidea. p. 60. PI. X. Figs. 1—4. PI. XI. 

 Figs. 7— 8. PI. XV. Fig. 2. 



— — var. tuberculata. Danielssen & Ko ren. Ibidem. 



p. 63. PI. X. Figs. 5— 7. PI. XV. Fig. 3. 



— — Levinsen. 1886. Kara-Havets Echinod. p. 399. 



PI. XXXIV. Fig. 9. 

 Rhegaster tiimidus Do der lein. 1900. "01ga"-Echinodermen. p. 219. 

 Taf. IX. Fig.l, la. 



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



tica. p. 459. 



— — Th. Mortensen. 1903. Echinoderms from East 



Greenland, p. 74. 



— — Michailovskij. 1903. Echinod. Russ. Exped. 



Spitzbergen, p. 26, 70. 

 Poraniomorpha (Rhegaster) tumida Grieg. 1906. "Michael Sars" Aste- 

 roidea. p. 34. Taf. I. Fig. 3. 



