VEGA-EXPEDITIONENS VETENSKAPLIGA ARBETEN. 459 
to trace out the limits of the species. Also were rich, but 
less interesting materials obtained from algee, collected near Cape 
Deschnew. Several samples of the bottom-mud from the North 
Siberian Sea were also taken, but in examining them I could 
not find a trace of diatoms. All the materials from the expe- 
dition of the Vega have been examined by myself. Still more 
materials from the hyperboreal America were collected during 
the British expedition under the command of Sir George 
Nares and examined by Mr. G. Dickie!. Afterwards I have 
received, through the kindness of Prof. Oliver, some of these 
samples. Among them only three were rich enough to be 
subjected to the usual cleaning-process, viz. from Bessel's Bay, 
817 N, Mushroom Point, 82228' N, and Discovery Bay, 81? 41". 
The result of my examination of these gatherings are to 
be found in the following pages. Also from the distant Franz 
Joseph Lånd some diatomaceous gatherings have been col- 
lected on the ice-flakes during the Austrian expedition under 
Weyprecht. Some of the species found by Mr. Grunow in 
these materials have been published in Van Heurck's Synop- 
sis and issued in Cl. and Möller Diat. No 314. Mr. Grunow 
will later publish in a more complete manner his researches 
in regard to these most interesting diatoms. The materials 
brought together from the Arctic Sea are thus very considerable, 
and their examination may give a tolerably complete idea of 
the diatomaceous vegetation the Arctic Sea. I have therefore 
tried to give in the following pages a complete list of all the 
arctic species, found by myself and by- Mr. Grunow, omitting 
those found by other authors, not beeing sure about their 
determinations. 
Index of marine arctic Diatoms. 
A. Placochromatice. 
I. Cocconeide2. 
Cocconeis Scutellum Ehb. (Van Heurck Syn. XXIX, 1—12) 
Greenl.,. Mushroom Point, Fr. J. L.”?, Spitsb., Finm., Kara, 
Cape Deschnew (East Cape). 
1 Jour. Linn. Soc. Vol. XVII, page 6. 
2 F. J. L. Franz Joseph Land according to Grunow. 
