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PACIFIC SCIENCE, Vol. XII, October, 1958 
PLANKTON HAUL AND DATE 
Fig. 3. Plankton settling volumes. 
’'transient”) lagoon plankton population 
compared with that reported from other 
northern Marshall Islands atolls (Johnson, 
1954). An analysis of the plankton dominants 
show that over half of the hauls were domi- 
nated by meroplanktonic forms, e.g., brach- 
yura zoea, or groups the majority of which 
are neritic, e.g., scyphozoan medusea. In 
some of the hauls, these forms made up 95 
per cent of the number of planktants col- 
lected. Certain of the species noted, e.g., 
Undinula vulgaris , have relatively long life 
cycles. For these and the noted meroplank- 
tonic forms to maintain the relative concen- 
trations indicated by these hauls would 
suggest a relatively stable body of lagoon 
water. The lack of numerous deep passes be- 
tween the ocean and the lagoon, common in 
other northern Marshall Islands atolls, might 
explain this indicated restriction in water 
exchange. 
REFERENCES 
Johnson, Martin W. 1954. Plankton of 
Northern Marshall Islands. Geol. Survey 
Prof. Paper 260-F. 
Tester, Albert L. 1954. Variation in egg 
and larva production of the anchovy, Stole- 
phorus purpureas Fowler, in Kaneohe Bay, 
Oahu, during 1950-1952. Pacific Sci. 9(1): 
31-42. 
