1909] Rohherflies of the Genus Asilus 139 



not know of a better way of accepting Williston's views on the 

 extent of the genus Asilus than to restrict it only by the descrip- 

 tion I have given above, and this would also agree with Schiner's 

 views so far as European species are concerned. Having reached 

 this conclusion I have worked out the synonymy accordingly, 

 so far as evidence could be obtained, and it develops that several 

 of the names that have been used as names of species in America 

 become untenable on account of having been used earlier as names 

 of species in the Old World. 



Macquart's studies in the subfamily in general preceded those 

 of Walker, but since the former writer used a number of names 

 that have been employed by older writers, he made some syno- 

 nyms which must give way to names which Walker gave to the 

 same species, and a similar condition exists in reference to the 

 work of the later authors. 



In his treatment of the Asilinae Lundbeck has followed Mik 

 in reference to the method used in referring to the color and the 

 arrangement of the bristles of the legs. When these organs are 

 stretched out at right angles to the body, the side which looks 

 forward is anterior. As this answers all purposes and is in use 

 it is adopted in this paper. 



I have received encouragement in this work from most of 

 the dipterists of the United States and take this opportunity 

 to express my appreciation of their good will. For the loan of 

 specimens, without which I could not have hoped to attempt this 

 paper, I am under obligations to the following museums and 

 private parties: The United States National Museum, including 

 an abundance of material collected by Coquillett on the Pacific 

 Coast; the Francis Huntington Snow Collection of Kansas Uni- 

 versity; the collection of the Massachusetts Agricultural College 

 and the collection of the University of Illinois. Chas. Dury, 

 Chas. W. Johnson, Dr. O. A. Johannsen, Dr. C. F. Adams, Dr. 

 W. A. Nason, Franklin Sherman, Jr., Dr. O. S. Westcott, S. A. 

 Rohwer, H. S. Harbeck, and Dr. Nathan Banks have loaned 

 or given me specimens from their own private collections 

 or from the collections of the institutions which they represent. 

 Furthermore Dr. W. D. Hunter, of the Bureau of Entomology, 

 Washington, D. C, has sent for study a large collection of Asilinae 

 collected during the time the studies of the cotton-boll weevil 

 and other species have been in progress in Texas. 



