Marine Plankton from the East-Greenland Sea. 277 



land, XVIII, 1895, p. 456, pi. 7, fig. 89; Gran, Norske Nordhavs Exp., Pro- 

 tophyta, 1897, p. 23, pi. 2, figs. 14—15; Nord. Plankton XIX, 1905, p. 92. 



Rare in the collection, only found in three samples from Dan- 

 marks Havn in Aug. — Septm. 1907, and, in a dwarfy state, in two 

 samples from the pack-ice in July 1908. 



Di strib. Northern neritic species, known from the coasts of Europe 

 and Arctic countries, further from Japan. 



28. Chaetoceras furcellatum Bail., American Journ. of sc. & arts, 

 ser. 2, vol. 22, 1856, pi. 1, fig. 4; Cleve u. Grunow, K. Svenska Vet. 

 Akad. Handl., Bd. 17, No. 2, 1880, p. 120, pi. 7, figs. 136—137; Gran, 

 Bibliotheca Botanica, Heft 42, 1897, p. 7, pi. 1, figs. 15—16; Nord. 

 Plankton, XIX, 1905, p. 95. 



Occurs as one of the characterizing species in a group of sam- 

 ples from the inner part of the pack-ice, in July 1908. Further some 

 C/ift'/oceras-chains in samples from Danmarks Havn in 1907 and in 

 the coastal water in 1908 may perhaps be referred to this species, 

 but the determination is not sure. 



Distrib. Arctic neritic species, known from the Arctic Seas, reaching 

 along the Norwegian coast as far soutliwards as Cape Stadt. 



29. Chaetoceras sociale Lauder, Transact. Microsc. Soc, vol. 12, 

 N. S., 1864, p. 77, pi. 8, fig. 1 ; Cleve, Bih. K. Svenska Vet. Akad. Handl., 

 Bd. 22, afd. 3, No. 4, 18'.I6, p. 9, pi. 2, fig. 9; Gran, Nord. Plankton XIX, 

 1905, p. 96, fig. 123. 



Occurs in great quantities in samples from Danmarks Havn in 



Aug.— Septm. 1907, and with resting spores. Further common in 



some samples from the coastal water in July 1908 and rare in 



others; also here mostly with resting spores. 



Distrib. Northern neritic species known from tlie coasts of Europe, 

 Iceland, Arctic countries and Hongkong. 



30. Chaetoceras gracile Schutt, Ber. Deutsch, bot. Ges., 1895, p. 42, 

 pi. 5, fig. 13; vix Paulsen, Medd. Komm. Havundersøg., Plankton I, 

 3, 1905. København, p. 5, figs. 6 — 7; non Apstein, Wiss. Meeresun- 

 ters., Abt. Kiel, N. F., Bd. 11, 1909, p. 135, fig. 1 ; C. septentrionale Cleve, 

 Bih. K. Svenska Vet. Akad. Handl., Bd. 22, afd. 3, No. 4, 1896, p. 9, 

 pi. 2, fig. 8; vix Østrup, Medd. Grønland, XVIII, 1895, p. 457, pi. 7, 

 fig. 88. 



In two samples from Danmarks Havn, August 1907, and in one 

 sample from the coast water, July 1908, I found a small solitary 

 Chœtoceras with resting spores. As m\^ figures (Fig. 10) show, it 

 must be identified with Cleve's C. septentrionale from Baffin Bay, 

 but hardly with Ostrup's original species of that name. On the 



