554 
Psyche 
[Vol. 92 
well as small beetles and true bugs. Circumstantial evidence suggests 
that the bee Agapostemon texanus is probably the most important 
pollinator. Future research should examine the specific nature of 
the insect-flower interactions. The simplified nature (fewer species 
of both plants and pollinators compared to similar mainland sites) 
of insect-plant interaction systems on the California Islands presents 
excellent opportunities for testing hypotheses of insect-plant inter- 
action and evolution (e.g. Cruden, 1972; Thorp, 1979). 
Acknowledgements 
We thank the National Park Service for permitting the research 
and for their assistance during the visit to San Miguel Island. Ralph 
N. Philbrick and Steve Junak, Santa Barbara Botanic Garden, 
enthusiastically assisted in fieldwork. We thank the following sys- 
tematists for identifications: N. Evenhuis, Bishop Museum (Bomby- 
liidae); R. J. Gill, California Department of Food and Agriculture 
(Coccidae); T. J. Henry, Systematic Entomology Laboratory, 
U.S.D. A. (Hemiptera); J. M. Kingsolver, SEL (Bruchidae and Mel- 
yridae); T. Kono, CDFA (Thysanoptera and Aphididae); A. S. 
Menke, SEL (Sphecidae); D. R. Miller, SEL (Coccidae); J. A. 
Powell, University of California, Berkeley (Tortricidae); T. N. 
Seeno, CDFA (Chrysomelidae); R. R. Snelling, Los Angeles 
County Museum (Apoidea); and F. C. Thompson, SEL (Syrphi- 
dae). R. J. McGinley, A. S. Menke, R. W. Rust, and R. R. Snelling 
reviewed the manuscript. 
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