.ART. 15. REVISION OF THE MUTILLID WASPS MICKEL. 3 



is inserted at the tip of the abdomen between the genitalia and the 

 last sternite, until the hook is pushed beyond the base of the cardo. 

 By a slight twist of the probe, the hook is brought into position to 

 catch at the base of the cardo and then withdrawn from the 

 abdomen, bringing the genitalia with it. With a little practice one 

 soon becomes skilful enough to remove the genitalia in this manner 

 without in any way injuring them or the specimen. The former 

 ■ are mounted on a paper point which is placed on the pin directly 

 beneath the specimen from which the genitalia were removed. 



On account of the fact that the various species of males may be 

 recognized by the use of external characters alone, I have not 

 ventured to make detailed descriptions of the genitalia. However, 

 in each case, except two, figures of the genitalia have been drawn by 

 the author either from the type specimen or from a specimen which 

 has been compared with the type. These figures present the dorsal 

 view of these structures as they lie in their normal position within 

 the abdomen. The figures are all drawn to the same scale; 1 mm. 

 in the drawing equals 0.0185 mm. in the genitalia. 



For the loan of material and the privilege of examining type speci- 

 mens in various collections I am indebted to the following: S. A. 

 Rohwer, United States National Museum; Dr. Henry Skinner, 

 American Entomological Society and Philadelphia Academy of 

 Sciences ; Dr. Frank E. Lutz, American Museum of Natural History ; 

 Dr. Nathan Banks, Museum of Comparative Zoology; Prof. S. J. 

 Hunter, University of Kansas; and Dr. J. C. Bradley, Cornell Uni- 

 versity. I am also indebted to the following persons for the loan of 

 material: Prof. Myron H. Swenk, University of Nebraska; Dr. J. 

 Bequaert, American Museum of Natural History ; Dr. C. P. Gillette, 

 Colorado State Agricultural College ; Prof. G. A. Dean, Kansas State 

 Agricultural College ; Prof. J. R. Parker and Prof. R. A. Cooley , Mon- 

 tana State Agricultural College; Dr. J. G. Sanders, Pennsylvania 

 Department of Agriculture; Prof. R. W. Doane, Leland Stanford 

 University; Prof. W. J. Chamberlin, Oregon State Agricultural Col- 

 lege; Dr. I. W. Hawley, Utah State Agricultural College; Dr. J. 

 McDunnough, Department of Agriculture of Canada; Prof. R. W. 

 Harned, Mississippi State Plant Board; Prof. C. S. Brimley, North 

 Carolina State College of Agriculture ; Prof. G. M. Bentley, Uni- 

 versity of Tennessee ; Prof. H. F. Wickham, Iowa State University ; 

 Prof. Don C. Mote, State Entomologist of Arizona : Mr. H. S. Smith. 

 California State Insectary; Prof. H. J. Reinhard, Texas State Agri- 

 cultural College; Prof. O. A. Stevens, North Dakota State Agri- 

 cultural College; and Mr. C. N. Ainslie, Sioux City, Iowa. To all 

 of these I wish to express my appreciation. I am also greatly in- 

 debted to Dr. William A. Riley and Dr. H. H. Knight for en- 

 couragement and helpful suggestions during the course -of this work. 



