VIM 



Preface 



so much to further our knowledge of the aquatic 

 insects of North America. 



Taxonomic work represents the fruition of the labors 

 of countless collectors and curators. In California, 

 field work and collections are recent, as compared 

 with many parts of the world, but are nonetheless 

 impressive. This work is based largely on the collec- 

 tions of the University of California Insect Survey 

 (Berkeley), the University of California collections 

 at Davis, Los Angeles, and Riverside, the California 

 Academy of Sciences (San Francisco), the Los Angeles 

 Museum, the San Diego Museum, and the personal 

 collections of the authors. Thanks are due to the 

 curators in charge of these collections, and especially 

 to E. S. Ross, J. N. Belkin, P. D. Hurd, and A. T. 

 MacClay. 



The illustrations may very well prove to be the 

 most useful part of this book. Acknowledgment is 

 given for each borrowed figure by citation in the 

 legend and by listing the original work in the bib- 

 liography at the end of each chapter. Original drawings 

 are mostly by Mrs. Celeste Green of the Department 

 of Entomology and Parasitology, University of Calif- 

 ornia, Berkeley (introduction and chapters 4, 10, 11, 

 and 13) and by Arthur Smith, at the British Museum 

 (Natural History) (chapter 7). Photographic work in 

 connection with illustrations was done by J. D. Lattin 

 and W. C. Bentinck. Several chapters have been read 

 and improvements suggested by Jon Herring. For 

 permission to use copyrighted figures we are indebted 

 to the following publishers and authors: University 

 of Toronto Press, E. M. Walker, The Odonata of 

 Canada and Alaska, 1953; Pennsylvania Fish Com- 

 mission, K. F. Lagler, Freshwater Fishery Biology; 

 John Wiley & Sons, Inc., G. C. Whipple, The Micro- 

 scopy of Drinking Water, 4th ed., 1927; The Macmillan 

 Company, E. 0. Essig, College Entomology, 1942; 

 Lane Publishing Company, Sunset Magazine; Univer- 

 sity of California Press, E. S. Ross, Insects Close 

 Up, 1953; Institute for Fisheries Research, Michigan 



Berkeley, California 

 June 12, 1956 



Department of Conservation, C. L. Hubbs and R. W. 

 Eschmeyer, The Improvement of Lakes for Fishing. 

 A Method of Fish Management, 1938; C. Wesenberg- 

 Lund, Biologie der Silsswasserinsekten; The Mac- 

 millan Company, E. 0. Essig, Insects of Western 

 North America, 1926; Entomologica Americana, A. G. 

 Boving and F. C. Craighead, An Illustrated Synopsis 

 of the Principal Larval Forms of the Order Coleoptera, 

 1931; Ohio State University, D. J. Borror and D. M. 

 Delong, An Introduction to the Study of Insects, 1954; 

 Ohio State University, Alvah Peterson, Larvae of 

 Insects; University of Toronto Press, F. Ruttner, 

 Fundamentals of Limnology, 1953; A. S. Barnes and 

 Company, J. Edson Leonard, Flies, 1950; Comstock 

 Publishing Company, Inc., J. G. Needham, J. R. 

 Traver, and Yin-Chi Hsu, The Biology of Mayflies, 

 1935; Comstock Publishing Company, Inc., R. Mathe- 

 son, Handbook of the Mosquitoes of North America, 

 1944; The Ronald Press Company, R. W. Pennak, 

 Fresh-water Invertebrates of the United States, copy- 

 right. 1953; W. B. Saunders Company, E. P. Odum, 

 Fundamentals of Ecology, 1953; American Museum of 

 Natural History, C. H. Curran, The Families and 

 Genera of North American Diptera; Ward's Natural 

 Science Establishment, Inc., How to Make an Insect 

 Collection; Scientific American, Inc., articles by E. S. 

 Deevey, Jr. and Ralf Eliassen; McGraw-Hill Book Co., 

 Inc., R. E. Snodgrass, Principles of Insect Mor- 

 phology, 1935; McGraw-Hill Book Company, Inc., 

 P. S. Welch, Limnology, 1952; Methuen and Company 

 Ltd., N. E. Hickin, Caddis, a short account of the 

 biology of British Caddis flies with special reference 

 to the immature stages, 1952; University of California 

 Press, J. G. Needham and M. J. Westfall, Jr., A Manual 

 of the Dragonflies of North America, 1955; Charles 

 C. Thomas, Publisher, P. W. Claassen, Plecoptera 

 Nymphs of America (North of Mexico), 1931; Charles 

 C. Thomas, Publisher, J. G. Needham and II. B. Hey- 

 wood, A Manual of the Dragonflies of North America, 

 1929; University of Florida, F. N. Young, The Water 

 Beetles of Florida, 1954. 



Robert L. Usinger 



