556 
PACIFIC SCIENCE, Vol. XV, October 1961 
CONCLUSIONS 
The data given above indicate that Velella is 
essentially carnivorous, feeding more or less in- 
discriminately on zooplankton primarily within 
the size range 0.2-10 mm. Motile organisms are 
not caught as effectively as nonmotile forms. 
Velella may be an important predator on fish 
eggs, which make up a major part of its diet. 
Euphausiid eggs are also an important part of 
its food. Off the California coast the seasonal 
appearance of Velella on the surface is corre- 
lated with the spring spawning of pelagic fish, 
such as hake, saury, sardine, and jack mackerel. 
The relatively greater abundance of suitable 
food during the spring months may be one of 
the factors responsible for the seasonal cycle 
of reproduction and growth in Velella. 
REFERENCES 
Bieri, R. 1959. Dimorphism and size distribu- 
tion in Velella and Physalia. Nat. 184: 1333— 
1334. 
Bieri, R., and D. H. Krinsley. 1958. Trace 
elements in the pelagic coelenterate, Velella 
lata. J. Mar. Res. 16(3): 246-254. 
Huxley, T. H. 1858. The Oceanic Hydrozoa. 
Ray Society, London. 141 pp. 
Lebour, M. V. 1947. An interesting young 
Velella in the Plymouth plankton. J. Mar. 
Biol. Assoc. 26: 548-550. 
S AVILOV, A. I. 1958. Pleuston of the western 
Pacific. Doklady Akad. Nauk SSSR 122(6): 
1014-1017. fin Russian.} 
Totten, A. K. 1954. Siphonophora of the In- 
dian Ocean, together with systematic and 
biological notes on related specimens from 
other oceans. Discovery Repts. 27: 1-162. 
Woltereck, R. 1904. Ueber die entwicklung 
der Velella aus einer in der Tiefe vorkom- 
menden Larve. Zool. Jahrb. Supp. VII, Fest- 
schrift A. Weismann: 347-372. 
