BIHANG TILL K. SV. VET.-AKAD. HANDL. BAND 22, AFD. III. N:0 4. 19 
as in the type. Transverse strize 10 in 0,01 mm., parallel, 
radiate at the ends.  Alveoli also 10 in 0,01 mm. — Pl. I, 1. 
This form is the same as ÖESTRUP figures (P1. IV f. 4) 
as Nav. didyma var., as I have convinced myself by inspec- 
tion of original specimens. 
Gomphonema exiguum var. pachyelada BRrRÉB. is to judge from 
specimens from east Greenland the same as G. septentrionale 
OrsSTE (pri dl4rP1 IE: 9): 
Gomphonema  kamtschaticum ' var. groenlandiea OEsTtR. This 
form, which is frequent in the Wankarema material, and has 
been named by GrRUNow in CL. & Mörr. Diat. 315—318 G. 
kamtschaticum var. siberica is to judge from original speci- 
mens the same as G. groenlandicum ÖESTR. (p. 414 P1. III 
för tl k2): 
Navicula decipiens CL. N.: Sp. V-. linear, with rounded 
ends, 0,04 to 0,05 mm. in length and 0,008 to 0,01 mm. in 
breadth. Axial area indistinct or very narrow. Central area 
an irregular, tramsverse fascia, frequently prolonged into 
narrow bands across the strie. Terminal nodules at some 
distance from the margin. Strie 14 to 16 in 0,01 mm. pa- 
rallel; radiate around the terminal nodules, not distinctly 
punctate, but frequently interrupted. — PI. I, 3, 4. 
This form has been figured by me as an extreme variety 
of GruNow's Nav. algida (Vega P1. LXXKXVII f. 41). It is 
doubtless the same as ÖrstTRUP's Nav. latefasciata var. angusta 
(P1. IV f. 35) of which Nav. seminflata ÖOzstr. (1. c. f. 39) 
seems to be a variety only. Also Nav. glacialis var. inequalis 
OzsTR. (P1: V f. 53) and var. angusta (1. c. f. 55) seem to be varie- 
ties of the same species, but have the strize split up in frag- 
ments, as is the case with so many other of the diatoms found 
on the iceflakes in the polar sea. The two last forms seem to 
be related to the former as Nav. erosa to Nav. transitans. 
The systematic place of this form is very uncertain. 
Perhaps it may be related to Pinnularia quadratarea. 
Navicula gelida var. perpusilla CL. =&L. 0,022; B. 0,007 mm. 
Strie 17 in 0,01 mm. parallel. This form resembles Nav. 
bahusiensis Özstr. (P1. IV f. 31), which however cannot be 
the species so named by GRUNOW, as the latter is far more 
delicate and has finer strie. I cannot identify this variety 
with ÖEsTtTRUP's fig. as the latter shews the strige radiate. — 
PR 
