Report on the Echinoderms of North-Kast Greenland. 271 



In the thick skin covering the adambulacral a. o. spines a great 

 number of cells occur containing a fine granular substance (PI. XVII. 

 Fig. 2). They may probably be mucus secreting cells. 



Ophiu roidea. 



15. Ophiopleura borealis Danielssen & Koren. 



PI. XIII. Figs. 7-8. 



Ophiopleura borealis Danielssen & Koren. 1877. Fra den Norske 

 Nordhavs-Expedition. Nyt Magas. for Naturv. 

 XXIII. p. 33. PI. V. Figs. 1-4. 



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



Sea p. 55. PI. IV. Figs. 1-21. 

 borealis Levinsen. 1886. Kara-Havets Echinod. p. 403. 

 PI. XXXV. Figs. 1-2. 



— — Fischer. 1886. Echinodermen. Oesterreich. 



Polarstat. Jan Mayen, p. 35. 



— — Grieg. 1893. Ophiuroidea. Norske Nordhavs- 



exped. p. 3. PI. I. Figs. 1—5. 



— — Grieg. 1900. Die Ophiuriden der Arktis. Fauna 



Arctica. p. 261. 



— — Grieg. 1903. Echinodermen von dem norwe- 



gischen Fischereidampfer "Michael Sars" in den 

 Jahren 1900—1903 gesammelt. 1. Ophiuroidea. 

 Bergens Mus. Årbog. 1903. p. 15. 

 — Th. Mortensen. 1903. Echinoderms from East 

 Greenland, p. 84. 



— — Koehler. 1909. Échinodermes. Monaco. XXXIV. 



p. 142. Pi. VI. Fig. 4. 



Stat. 99 (77" N. 171/2° W.) 300 m. Several specimens, of different sizes, 

 from 3 to 35 mm diameter of disk. The genital slits have 

 appeared already in the smallest specimens. 



One specimen shows a very curious abnormality. It looks as if 

 part of the disk with the corresponding arm has been cut off and 

 the arm alone reproduced. Whether this has reall}^ been the case 

 cannot be ascertained; but in any case it has seemed to me worth 

 figuring the curious specimen (PI. XIII. Figs. 7 — 8). 



16. Opliioglyplia robusta (Ayr.). 

 PI. XVI. Fig. 1. 



Ophiiira squamosa Lütken. 1857. Grønlands Echinod. p. 50. 

 — — — 1858. Additamenta ad historian! Ophiu- 



19* 



