SMICRONYX WEEVILS—ANDERSON 187 
ments between certain species is that of Snedecor (1956, pp. 244-245, 
250) whose test criterion, or F value, is based on the ratio. 
mean square of sample means, 
mean square of individuals 
TERMINOLOGY 
The definitions of most of the terms used in this study are found in 
the glossary published by Torre-Bueno (1937). However, the terms 
used in reference to genitalia are those used by Bissel (1937) and by 
Bruhn (1947). The terms used in discussions of geographic distri- 
butions are those used by A. K. Lobeck in his ‘“‘Physiographic Prov- 
inces of North America” (1948), published by Columbia University. 
ACKNOWLEDGMENTS 
I wish to express my thanks to Dr. J. G. Franclemont of Cornell 
University, under whose guidance this work was carried out, for his 
advice concerning the manuscript and for his help in many other ways. 
Dr. R. T. Clausen and Dr. C. E. Palm, of the same institution, were 
also very helpful in reading and criticizing the manuscript. 
Thanks are also due the following entomologists for their coopera- 
tion in connection with the loan of material and, to some of them, for 
the courtesies extended to me during my visits to the collections 
under their care: Dr. Henry Dietrich, Cornell University; Dr. W. H. 
Anderson and Miss R. E. Warner, U.S. Department of Agriculture, 
at the U.S. National Museum; Dr. G. E. Wallace, Carnegie Museum; 
Mr. H. B. Leech, California Academy of Sciences; Dr. W. J. Brown 
and Dr. H. F. Howden, Science Service, Ottawa; Mr. Henry Dybas, 
Chicago Natural History Museum; Dr. M. A. Cazier and Mrs. 
Patricia Vaurie, American Museum of Natural History; Dr. F. S. 
Truxal, Los Angeles County Museum; Dr. P. J. Darlington, Jr., and 
Dr. W. L. Brown, Museum of Comparative Zoology, Harvard Uni- 
versity; Dr. Harold Grant, Academy of Natural Sciences, Philadel- 
phia; Dr. Rene Malaise, Naturhistoriska Riksmuseum, Stockholm; 
Dr. Leland Chandler and Dr. J. V. Osmun, Purdue University; Dr. S. 
W. Frost, Penn State University; Dr. Barry D. Valentine, Ohio 
State University; Dr. Elbert L. Sleeper, Long Beach State College. 
I am indebted to my mother, Mrs. J. K. Anderson, for her services 
in typing portions of the first draft of the manuscript, and to Miss 
Frances Ann McKittrick for her aid with the illustrations. 
HISTORY 
The nomenclatorial history of the genus Smicronyr began in 1836 
when Schoenherr proposed the name Micronyz for a group of seven 
