M. J. West-Eberhard, Universidad del Valle, 

 Call, Colombia, and R. R. Snelling reviewed 

 the manuscript on Vespidae and supplied 

 data on taxonomy and biology. J. E. Gillaspy, 

 Texas A & I University, Kingsville, provided 

 information on PoHsfes Latr. 



H. E. Evans reviewed the manuscript on 

 Pompilidae, and F. E. Kurczewski, University 

 of Syracuse, N. Y., contributed some prey 

 records. 



R. M. Bohart and A. S. Menke generously 

 made available a copy of their manuscript, 

 "Sphecid Wasps of the World," which was 

 most helpful in assembling the section on 

 Sphecoidea ; Menke, in addition, reviewed the 

 catalog manuscript for this superfamily. 

 Other specialists contributed data on the 

 groups mentioned after their names : R. E. 

 Coville, University of California, Berkeley 

 (taxonomy and distribution of Trypoxyloni- 

 nae) ; J. E. Gillaspy (Bembicinae) ; F. E. 

 Kurczewski (biology of Larridae and Cra- 

 bronidae) ; R. C. Miller, Cornell University 

 (taxonomy, distribution, and biology of 

 Crabronidae) ; W. J. Pulawski, Wroclaw, 

 Poland (taxonomy and distribution of Tachij- 

 sphe.r Kohl) ; and D. Vincent. University of 

 Maryland, College Park (taxonomy and dis- 

 tribution of Passaloeciis Shuck.). 



E. G. Linsley, University of California, 

 Berkeley, reviewed the entire manuscript on 

 Apoidea and offered valuable suggestions. 

 C. D. Michener, University of Kansas, Law- 

 rence, discussed with the author of that sec- 

 tion the biology and systematics of bees; 

 many of his suggestions have been incorpo- 

 rated in the classification adopted. The fol- 

 lowing specialists have cooperated by con- 

 tributing data on the groups specified after 

 their names: G. E. Bohart, Bee Biology and 

 Systematics Laboratory, Utah State Univer- 

 sity, Logan (taxonomy and biology of 

 Apoidea) ; W. E. LaBerge, Illinois Natural 

 History Survey, Urbana (taxonomy of An- 

 drenidae and Anthophoridae) ; U. N. Lanham, 

 University of Colorado, Boulder (taxonomy 

 of Apoidea) ; M. A. Lieftinck, Rhenen, The 

 Netherlands (taxonomy of Anthophoridae) ; 

 A. L0ken, University of Bergen, Norway 

 (taxonomy of Apidae) ; T. B. Mitchell, North 

 Carolina State University, Raleigh (taxon- 

 omy of Apoidea) ; J. S. Moure, Universidade 



Federal do Parana, Curitiba, Brazil (taxon- 

 omy of Apoidea) ; F. D. Parker (taxonomy 

 and biology of Apoidea) ; J. G. Rozen, Jr., 

 American Museum of Natural History, New 

 York, New York (taxonomy and biology of 

 Apoidea) ; R. R. Snelling (taxonomy of 

 Hylaeus F.) ; R. W. Thorp, University of 

 California, Davis (taxonomy and biology of 

 Apidae) ; P. H. Timberlake, University of 

 California, Riverside (taxonomy of Apoidea) ; 

 and T. J. Zavortink, University of San 

 Francisco, California (taxonomy of Antho- 

 phoridae) . 



C. W. Sabrosky (SEL) has been helpful to 

 all of us in the discussion of abstruse nomen- 

 clatural problems. J. F. Gates Clarke (SI) 

 participated patiently in philosophical dis- 

 cussions of a wide variety of subjects per- 

 taining to the catalog. G. C. Steyskal (SEL) 

 was the resource person for the grammar of 

 scientific names and other linguistic matters. 



Computerization of the catalog and its pro- 

 duction by the computer-driven Linotron re- 

 quired the highly skilled technical expertise 

 of specialists in computer storage and appli- 

 cations. James F. Hello, formerly Chief of the 

 Data Processing (ADP) Program at NMNH, 

 carefully analyzed the 1951 Hymenoptera 

 Catalog and developed the data analysis 

 matrix which governed entry of information 

 into the computer. R. Creighton, Manager, 

 Information Retrieval and Indexing Division, 

 Office of Computer Services (OCS), SI, de- 

 vised the programs for editing, arranging, 

 querying, and displaying data from the man- 

 uscripts. J. J. Crockett, Manager, Software 

 Systems and Program Maintenance (OCS), 

 developed the program for conversion of the 

 computerized data to special magnetic tapes 

 capable of driving the Photo Typesetting 

 Unit, the Mergenthaler Linotron 1010, in the 

 Government Printing Office. T. G. Gautier, 

 Chief (ADP), and D. Bridge, Operations 

 Manager (ADP), maintained daily collabora- 

 tion with the Editorial Board in assignment 

 of clerical assistance, and production of the 

 edit phases, merge files, and SELGPO print- 

 outs. 



Finally, we are most grateful for the care- 

 ful, accurate typing of the manuscripts for 

 computer entry by the corps of dedicated 

 clerk typists. R. M. Garlick served with the 



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