Report on the Echinoderms of North-East Greenland. 255 



Pontaster tenuispimis S lad en. 1889. Asteroidea of the "Challen- 

 ger", p. 28. 



— — Bell. 1892. On the Characters and Variations 



of Pontaster tenuispinus. Proc. Zool. Soc. p. 430. 

 PI. XXVI. 



— — Bell. 1892. Catalogue of British Echinoderms. 



p. 60. 

 Archaster — Levinsen. 1896. Kara-Havets Echinodermata. 



p. 401. PI. XXXIV. Figs. 10— 11. 

 Pontaster — Ludwig. 1900. Arktische Seesterne. Fauna 



Arctica. p. 447. 



— — Michailovskij. 1903. Echinod. Russ. Exp. 



Spitzbergen, p. 29. 



— — Grieg. 1906. "Michael Sars" Asteroidea. p. 3. 



— — Ko eh 1er. 1909. Echinodermes. Monaco. Ease. 



XXXIV. p. 10. Pl.X. Figs. 1—4. PI. XII. Fig. 6. 



— — Sussbach u. Breckner. 1910. Die Seeigel, 



Seesterne u. Schlangensterne der Nord- u. Ostsee. 

 Wiss. Meeresunters. Abt. Kiel. N. F. Bd. 12. p. 201. 



Station 99 (77° N. 171/2° V^^.) 300 m. One small specimen. R. = 6mm. 



The larger central spine of the paxillæ has not yet made its 

 appearance, except in a few of those in the outer end of the arms, 

 where the central spine is slightly longer than the outer ones. Pedi- 

 cellariæ are not developed on the adambulacral plates. On the 

 other hand, I find some small pedicellariæ on the upper marginal 

 plates in the inner part of the arms. Also in larger specimens pedi- 

 cellariæ generally occur here, placed near the edge between the 

 upper and lower marginal plates, now at the inner end of the arm, 

 now more at the outer end. It appears that these pedicellariæ 

 have not hitherto been observed. They occur, it should be noticed, 

 also in specimens with the adambulacral pedicellariæ well developed. 

 They are considerably smaller than the adambulacral pedicellariæ 

 and consist of 3—5, generally 4, of the usual small spines placed 

 close together so as to be able to act against one another; the spines 

 are not specialized in any way, so it is a very primitive kind of 

 pedicellariæ. 



5. Ctenodiscus crispatus (Retz.). 



PI. XIV. Figs. 4, 6. PI. XVI. Figs. 4-5. 



Ctenodiscus crispatus Lütken. 1857. Grønlands Echinodermata. 



p. 45. 



— — Sars. 1861. Norges Echinodermer. p. 26. 



18* 



