Full text from the Biodiversity Heritage Library.

The complete title of this book is "Aquatic Insects of California---with keys to North American Genera and California Species". So the keys to genera may be useful for BugGuide users far beyond California.

Usinger provides a 45 page introduction to aquatic entomology, the second half of which deals mostly with pest control issues. The remainder of the 508 page book has chapters written by various authors on aquatic Collembola, Ephemeroptera, Odonata, Orthoptera, Plecoptera, Hemiptera, Megaloptera, Neuroptera, Trichoptera, Lepidoptera, Hymenoptera, Coleoptera, and Diptera.

Though obviously dated, this is still a useful reference...in fact, a recent article praises it as "a landmark event and unique collaboration in benthic biology". Moveover, a supporting Essig Museum link provides links to PDF's with updated checklists and bibliographic references. The Essig Museum also has a nice biographical sketch of Robert L. Usinger, the editor and a major contributing author.

For a more detailed and erudite review, from a 1957 volume of the journal Limnology and Oceanography, scroll to the bottom of the first page of this PDF (210 KB).