2 CYRTIDAE OF NORTH AMERICA 



special study of the group and, as 'Some of the articles are not 

 easily accessible, notes from these have been incorporated in this 

 paper. 



Life history and habit notes are included in this synopsis, as 

 they are of general interest and a great aid to the knowledge of 

 the species; the larval and pupal characters may, when known, 

 serve to separate some of the closely allied species and establish 

 the relationships of the genera. 



The writer wishes to acknowledge the generous loan of material 

 by the following: the late Mr. Frederick Knab of the National 

 Museum; Mr. C. W. Johnson of the Boston Society of Natural 

 History, who also loaned his large personal collection; Mr. M. C. 

 Van Duzee; Dr. J. M. Aldrich; Prof. A. L. Melander; Mr. W. 

 R. Walton; Mr. C. T. Greene; Mr. E. T. Cresson, Jr. and Prof. 

 R. W. Doane. The Cornell University collection was obtained 

 through the kindness of Mr. R. C. Shannon and Professor Brad- 

 ley. Mr. Nathan Banks loaned his private collection and a num- 

 ber of specimens from the Museum of Comparative Zoology at 

 Cambridge. I am also indebted to Prof. S. J. Hunter for the 

 loan of the Kansas University material. Even with all these col- 

 lections material is all too scarce and I cannot establish some of 

 the species to my entire satisfaction. The types should all be 

 examined and compared, especially the types of Westwood's 

 species, of which one cannot be certain because of the two or three 

 line descriptions. 



Parasitism, among other agencies, has produced some curious 

 modifications of the family type in the Cyrtidae and we see marks 

 of degeneration. Wiedemann gave them the name of "fat- 

 flies," because of their generally inflated balloon-like bodies. 

 The common name of ''small-headed flies" was given them by 

 Comstock in his Manual; they might well be called "Swollen- 

 bodied flies." 



The drawings have been made from specimens, using a bin- 

 ocular microscope, and care has been taken to make them as accu- 

 rate as possible, so that they would supplement the descriptions 

 and aid in establishing some of the uncertain species. There is 

 often quite a variation in marking and color, but most of the 

 species have a "habitus." Important characters may be found in 

 the genitalia when more work is done and dissections made. 



