Central Pacific Salpidae — YOUNT 
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Fig. 6. Cruise 8, 172° W. longitude, a, Relationship of total salp volume, total salp numbers, and numbers of 
Thalia democratica to major currents, upwelling, and island masses. Limits of currents, upwelling, and islands are 
approximate, b , Relationship of the other common species, Salpa fusiformis , Ritteriella amboinensis, and Cyclosalpa 
pinnata to major factors listed in a. 
being less abundant than Salpa fusiformis off 
the coast of California; this is perhaps a result 
of the lower temperatures in California waters. 
RELATIVE IMPORTANCE OF DOMINANT SALP 
SPECIES IN THE CENTRAL PACIFIC 
Frequency of occurrence by station 
Cruise 5 
1. Thalia democratica 
2. Ritteriella 
amboinensis 
3. Salpa fusiformis 
Cruise 8 
Thalia democratica 
Salpa fusiformis 
Ritteriella amboinensis 
and Cyclosalpa pinnata 
Numerical ranking of species 
1. Thalia democratica Thalia democratica 
2. Salpa fusiformis Traustedtia multitenta- 
culata 
3. Ritteriella Salpa fusiformis 
amboinensis 
Frequency of dominance by volume 
1 . I as is zonaria and Ritteriella amboinensis 
Ritteriella and Thalia 
amboinensis democratica 
2. Thalia democratica Salpa fusiformis 
