Xaa den norske Nordhavs-expedition 1876 — 78 Idev 

 der af professor Dr. G. 0. Sårs indsamlet endel pJunldon 

 fra overfladen; skjont disse prøver væsentlig- indeholder 

 alger, især Diafomaceer, har de dos vakt den Ijeromte 

 zoologs interesse, og lian liar under selve expeditionen ud- 

 fort en række vellykkede tegninger af de mest karakteri- 

 stiske former. Da jeg sidste vaar fik proverno til bearbei- 

 delse, var lian saa velvillig at laaiie mig tegningerne til 

 benyttelse. 



Prøverne indeholder saagodtsom udelukkende vegeta- 

 bilsk planldon. Diatomaceer, CiJioflageUater og SUifoflarjel- 

 later; knn paa en enkelt station (296) tindes en jn-otozo, 

 Tintimms deuikuJaius. Ehr., i smaa mængder; jeg vil derfor 

 i dette arbeide kun liehandle Nordhavets pelagiske proto- 

 phytflora. 



Der er kun samlet idankton fra i't forholdsvis lidet 

 antal stationer; enkelte af proveriie er desuden delvis øde- 

 lagte, idet spiritussen er torret ind: disse har jeg raaattet 

 koge med salpetersyre, hvorved cilioflagellaterne destrueres, 

 og alene diatomaceer og silicoflagellater kan undersøges. 



Disse provers indliold vil derfor kun give et ufuld- 

 stændigt billede af Nordhavets planktoiitlora; men ved 

 senere indsamlinger er de supplerede. Saaledes har Dr. 

 Johan Hjort samlet plankton ved Norges kyster til forskjel- 

 lige aarstider i 1893—95 (kfr. EjoH, 1895, p. 38 ff.), cand. 

 real. Nordgaard ved vestkysten fra Stavanger til Lofoten 

 i februar — april 1896 og i Bergenslj orden i juni — august 

 s. a., marinekaptein S. Muller ved vestkysten i juni 1896, 

 og paa Dr. Hjorts foranstaltning fulgte kaptein Bie med 

 chefskibet ..Heimdal" paa dets ishavstogt i mai 1896 og 

 samlede plankton paa opturen; i sommeren 1896 har 

 kaptein Haslum i Atlanterhavets nordvestlige del samlet 

 endel prover, som professor W/IIe har overladt mig til 

 undersøgelse. 



Desuden jiar dels frk. Kristine Botuievie, dels jeg selv 

 samlet plankton til forskjellige tider i Christianiafjorden, 

 især ved Drøbak, og professor Viere bar velvillifi overladt 

 mig en prøve fra Bohusliln (november 1893). 



D, 



'uring the Norwegian North Atlantic Expedition, 

 1876 — 78, a quantity of phinlxtoit \vas collected from the 

 surface liy Prof. G. 0. Sårs. Although these samples 

 contained mainly algre, especially Diatomaceæ, they aroused 

 the interest of that famous zoologist, and even during the 

 expedition, he executed a series of successful drawings of 

 the most characteristic forms. When I received the samples, 

 in the spring of 1896, for investigation, Prof. Sårs was 

 kind enough to place his drawings at my disposal. 



The samples contaiu alraost exclusively vegetable 

 2)lanMoii. Diatomaceæ, CilioflageUata and Silicoflagellata; 

 at only one station (296) was a protozoen found, — Tiii- 

 tinirns dentiadatus, Ehr. — in small ijuantities. In this 

 paper I will therefore only treat of the pelagic protophytic 

 flora of the North Atlantic. 



Plankton was collected at only a comiiaratively small 

 nuniber of stations. A few of the samples, moreover, were 

 partial ly destroyed through the drying up of the alcohol, 

 and these I was obliged to boil in nitric acid, thereby 

 destroying the CilioflageUata; so that only the Diatomaceæ 

 and Silicoflagellata could be exarained. 



The contents of the samples will therefore give only 

 an incomplete rejiresentation of the plankton flcn-a ot the 

 North Atlantic; hut it is suppleraented by subsequent 

 collections. Dr. .Toli. Hjort collected plankton on the coasts 

 of Norway at different seasons of the year, during the years 

 1893—95 (cf. Hjort, 1895, p. 38, etc); Mr. Nordgaard 

 on the west coast from Stavanger to Lofoten in February, 

 March and April, 1896, and in the Bergen Fjord in June, 

 July and August of the same year; Capt. S. Midler. R. N. 

 on the west coast in June, 1896; and by Dr. Hjorfs di- 

 rections, Capt. Bie accompanied the ship ,.Heimdal" on 

 her arctic cruise in May, 1896, and collected plankton on 

 the outward voyage ; and in the summer of 1896, Capt, 

 Haslum collected some samples from the north-western 

 parts of the Atlantic, whicb Prof. WilJe has handed over 

 to me for exaniination. 



In addition to these. Miss Kristine Bonnevie and I 

 have each collected plankton at various times from the 

 Christiania Fjord, especially at Drøbak; and Prof. Qeve 

 has kindly sent me a sample from Bohusliin (Nov, 1893). 



