BIHANG TILL K. SV. VET.-AKAD. HANDL. BAND 22. AFD. III. N:o 4. 7 
the west coast of Sweden, in the south western Baltic, also 
in the English Channel and on the south coast of Bretagne. 
Chetoceros decipiens CL. occurs sparingly in most samples, 
but abundantly in the October-plankton. It is an atlantic 
species, found abundantly south of Iceland, also on the west 
coast of Sweden. 
Dimensions: long. ax. 0,008; sag. ax. 0,014; tramsv. ax. 
0,008 mm. 
Chetoceros furcellatus (BAIL.) CL. — Chains membranaceous 
of 3 to many cellules, somewhat twisted, sometimes curved. 
Foramina very narrow. dCellules in the sagittal-view !) qua- 
drate, in the transversal view broadly elliptical to almost 
orbicular. The awns marginal, with very short basis, filiform, 
curved, in the transversal view diverging in a right angle. 
Terminal awns not stronger than the others. Endocysts in 
transversal view elliptical, with two very strong diagonal 
awns, in sagittal view with more or less conical, finally 
puncetate valves. From the connecting zone issue in the 
sagittal direction two strong, furcate awns. Dimensions: long 
AUG; SAd. AL ÖL TS: GYANSVA dn 0009 mMmm.; AWIAS- IN 
length 0,09 mm. — PI. II 6, 7. 
BV 0 fice ta fun es (IBATR.) GRUN. Afrets DÅ pu 120 PVE 
f. 136, 137 (endocysts). Chet. vermiculus SocHört Ber. D. Bot. 
Ges. 1895 p. 39 (chains). 
This species seems to be widely distributed among others 
found in sea of Kara, in the south-western part of the Baltic, 
in the northern Atlantic and in Davis Strait. It occurs spa- 
ringly in the August- and October-plankton of Baffins Bay. 
Chetoceros groenlandicus CL. N. sp. Chains straight, multi- 
cellular, rigid, their form remaining almost unaltered after 
ignition. Foramina smaller than the cellules, narrow sub- 
hexagonal. Cellules in the sagittal view nearly quadrate, 
with slightly concave margins. Valves concave, elliptical. 
Dimensions: long. ax. 0,016 to 0,028; sag. ax. 0,022 to 0,038; 
transv. ax. 0,012 mm. Awns arising near the margin, their 
bases short (0,004 mm.) diagonal and longitudinal, their pro- 
longations slightly curved, two sagittal and two contrary 
transversal. Terminal awns stronger than the others, di- 
1 I use the terms proposed by ScHöTtTt in his paper on Chzetoceros in 
Ber. .d. Deut. Bot. Ges. 1895. 
