| 
| 
| 
137 
1/8 of the length of the cell. Chromatophore 
1, in front, large with turned løbes. ÅAwns 
straight, stiff, very long, issuing from the 
angles of the cell, crossing one another at 
the insertion; two of them proceed in a sa- 
gittal direction, two diverging from the. first 
at acute angles ; terminal. awns diverging, in 
a front view, at a largely  obtuse angle. 
Spores unknown. 
Fig.7. Chætoceras 
Beslægtet med -C. bottnicum og C. cas- rigidum Ostf. 
Ppicum, men adskilt ved de stærkt diverge- 
rende Terminalhorn. 
a. Kæde i ntstilling ; 
b. Sidestilling. €&%/). 
11. CC. simplex nm. sp. 
Cells solitary or two together, in a front view rectangular, 
wider than long (12—16 4 long, 16—24p wide), in a side view 
elliptic. Valves concave with a slight convexity in the middle. 
Chromatophore 1, situated 
cløse tø the one valve. Awns Em mn see 
delicate, very long, issuing =—< TET >———— 
(2 
From the angles or a little 
within the angles, then tur- a 
ning sharply off, all in sa- Fig.8. Chætoceras simplex Ostf. 
i irection : a. Celle i Sidestilling; 6, c. Frontstilling. 
gittal direction; often the (04). 
two awns to the same side 
cross one another at the basal thirdpart; in & side view the awns 
are nearly parallel. Spores. unknown. 
Beslægtet med de to andre enlige Arter, C. gracile Schiitt og 
C. septentrionale Oestr., men adskilt ved den ene Kromatofor og 
Hornenes Forløb. 
12. Coscinodiscus radiatus Ehbg., s.1. 
13.… Melosira. Borreri. Grev., var. subglobosa Grunow, 1.6. 
Pp. 128, Pl. 4, f. 13. 
