MARINE BIOLOGICAL STATION AT PORT ERIN. 69 
Dharend 
e Sagitta 
# Ockhopleara 
ce Dinoflogellata 
B. Copspoda 
Fig. 19. Be showing maximum hauls in the year 1907. 
Lists compiled from the gatherings and curves drawn 
from these lists show that, as a consequence of the three 
factors noted above, certain groups and certain prominent 
species differed from one another greatly in their relative 
abundance throughout the months of the year (see fig. 20). 
Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec. 
DG) 
|__| Dit ns ee 
Dinoflagellates ie 
Ceratium 
Sagitta 
Tomopteris 
Copepoda 
Microcalanus 
Anomalocera 
Centropages 
Temora 
Cladocera 
Oikopleura 
Total Plankton 
} 
Fic. 20. Distribution throughout the year 1907—diagrammatic. 
