20 P. T. CLEVE, THE PLANKTON Of THE NORTH SEA, ENGLISH CHANNEL, ETC. 



Chlorophyllaceae. 



Halosphrera viridis Schmitz. — January: Väderö and Måseskär c r. February: 

 Plym. re; between Scotland, SW. Norway and Skagen more or less common; Skagerak + r. 

 Marek: Plym. + r; N. of »Scotland r; Skagerak ccr. April, May: between Scotland, SW. 

 Norway and Skagen, as a rnle rare; Maseskär + r; Väderö c. July, August: Hebrides +. 

 E. of Scotland v. September: Plym. r. October: Plym. r +; Skagerak r. November: 

 Plym. r; Hebrides r; round Scotland and across the North Sea to SW. Norway and 

 Skagen; Skagerak r. December: Plym. r; Måseskär r; Väderö +. 



Dinoflagellatae. 



Ceratium (tripos var.) bncephalum Cl. — January: Väderö and Måseskär + r. Fe- 

 bruary: area between S. Norway, Skagen, 56° N. 3° E. and 58° N. 2° E. as a rule not rare; 

 \ r äderö r. April, May: 56°— 57° N. 4° E. rr; 58° N. 4° E. and 59° N. 2° E. r. July, 

 August: 57° N. 4°— 6° E. and 56° N. 2° E. r; Skagerak + r. September: Skagerak r. No- 

 vember: more or less common on the area between S. Norway, Skagen, 56° N. 1° E. and 

 58° N. 2° E. Skagerak r. December: Väderö + r. 



C. furca Duj. — January: Måseskär + r. February: area between Newcastle, S. 

 Norway and Skagen cc; N. of the Dutch coast r; W. of Jutland +. March: Plym. ?•; 

 N. of Scotland r; Skagerak r. April, May: from 61° N. 1° E. to the Skagerak r, at 58° 

 -59° N. 3°— 2°E. c; area between 58° N. 5° E, 57° N. 2° E. and 56° N. 7° E., rare or dead. 

 June: S. and W. of Norway c; Skagerak er. July, August: Plym. + /■; off Heligoland c; 

 between the Shetlands, Scotland and Norway cc, Skagerak + r. September: 58° — 59° N. 

 7° — 5° E. + r; Skagerak r. October: Plym. r; Väderö r. November: Irish Sea c; area 

 between Newcastle, 58° N. 2° E., Skagen and 55° N. 6° E. ; Skagerak +. December: Skage- 

 rak + r. 



€. fusus Duj. — January: Helder r; Väderö and Måseskär + r. February: Plym. r; 

 Helder +; between Firth of Tay, S. Norway and Skagen, as a rnle r; along the W. coast 

 of Denmark c +. March: Plym. r; Väderö r. April, May: Plym. er; area between 

 60° N. 2°E., 57° N. 1° E. and Jutland, as a rule rare, but common at 59° N. 2°E.; 

 Måseskär + rr. June: Plym. re; Helder r; 59° N. 5° E. +; Maseskär + r. July, August: 

 Plym. r; N. of Scotland r; 58° N. 0° W. to 61° N. 2° E. c +; W. Skagerak to 56° N. 3° E., 

 as a rule rare; Skagerak re. September: 59° N. 5° E. c; 58° N. 7° E. r; Skagerak er. 

 October: Väderö c. r. November: Irish Sea; from E. Scotland and N. England to Skagerak 

 and the W. of Jutland; Skagerak er. December: Väderö r. 



C. lineatum En b. — February: off S. Norway and on a spöt in the centre of the 

 North Sen. May: 58° N. 5° E. r. July: 58° N. 6° E. r. September to December: Skagerak r. 



