2 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. Ill 



dice, together with a study of the Uterature, convinced the writer that 

 adequate generic and specific characters could not be drawn from an 

 investigation Hmited to the Elateridae of Saskatchewan, or from super- 

 ficial studies covering a larger region. Instead, he concluded that true 

 generic and specific characters could be obtained only through an in- 

 tensive comparative study involving all available species of the group 

 under investigation. 



The present study, which deals particularly with the genus Ludiiis 

 Eschscholtz, is based upon these principles. In the broad sense it 

 consists of two parts : a detailed treatment of all available identified 

 Ludiiis larvae in the world, and a comprehensive survey of the larval 

 morphology of the other genera included by Hyslop (1917) in the 

 tribe Lepturoidini. The investigation was discontinued in 1942 and is 

 believed to be a reasonably complete record and analysis of the perti- 

 nent information available at that time. Only mature or nearly ma- 

 ture larvae are considered. The 93 species included represent 11 

 genera as follows: Athons (14), Crepidomemis (i), Cryptohypnus 

 (5), Eanus (2), Elathous (i), Hemicrepidius (5), Hypnoidus (3), 

 Lepturoides (3), Linionhis (14), Ludius (44), and Melanactes (i). 

 It is essentially a study in detail and will be used most conveniently 

 by workers who have a knowledge of the basic morphology of ela- 

 terid larvae as outlined by Glen, King, and Arnason (1943). 



ACKNOWLEDGMENTS 



By far the greater part of this study was conducted at the Dominion 

 Entomological Laboratory, Saskatoon, Saskatchewan. However, more 

 than 6 months' intensive research was done in 1936-37 at the United 

 States National Museum, Washington, D. C, and considerable time 

 was devoted to this project at the University of Minnesota, INIinne- 

 apolis, Minn., where the writer was privileged to work under a Caleb 

 Dorr Fellowship for 1931-32 and a Shevlin Fellowship for 1932-33. 



With deep appreciation the writer acknowledges his indebtedness 

 to these institutions and to the many friends and associates who have 

 given stimulating and helpful advice throughout the study. Special 

 acknowledgment of assistance is due Dr. Kenneth M. King, formerly 

 in charge of the Saskatoon laboratory, who contributed so much to 

 the viewpoint, the plan, and the methods adopted, and with whom 

 constant consultation has been a valuable privilege ; Dr. A. G. Boving, 

 formerly senior entomologist, United States Bureau of Entomology 

 and Plant Quarantine, Washington, D. C., whose counsel and gui- 

 dance have been of lasting benefit ; Dr. C. E. Mickel, Professor of 



