THIS VOLUME 



IS RESPECTFULLY DEDICATED TO 



DR. CARL W. VON DALLA TORRE 



THE EMINENT BOTANIST AND HYMENOPTERIST, PROFESSOR IN THE 

 UNIVERSITY OF INNSBRUCK, WHO, IN THE COMPILATION OF 

 "CATALOGUS HYMENOPTERORUM," HAS DONE SO 

 MUCH FOR WORKING HYMENOPTERISTS 



THE AUTHOR 

 Washington, D. C, January, 1901 



