14 PROC. ENT. SOC. WASH., VOL. 22, NO. I, JAN., 1920 



In, fact, from various points of view the Asilidae can be com- 

 mended to students, as a wonderfully interesting group, 

 which certainly will well repay further collection and study. 



It is rather surprising, for instance, that in a family of flies of 

 as large average size and conspicuous habits as the Asilidae, and 

 in a collection as well-worked from a locality as the vicinity of 

 Washington, it has been necessary during the preparation of this 

 paper, to describe as new no fewer than 1 1 forms. While identifying 

 material for the purposes of the present list Mr. Banks found 

 and described two new species in Asilus, one each in Leptogaster 

 and Dasyllis, and a new species and new variety in the genus 

 Dioctria. Revisions of the last three of these genera were pre- 

 pared b'y Mr. Banks, and the genus Laphria was revised by Mr. 

 McAtee, the latter work resulting in the description of five new 

 species from the Washington region. Previously 8 new names 

 had been based in whole or in part upon District of Columbia 

 material. One of these names was proposed merely as a sub- 

 stitute for an older but unavailable name, and two of them are 

 now placed in synonymy. 



The total number of species in the following list is S3. 1 ' 2 For 

 comparison it may be stated that 69 species of Asilidae are listed 

 in the Insects of New Jersey, 3 and 51 species in the Diptera of 

 Florida. 4 



Described species in addition to those hereafter listed which 

 may reasonably be expected to occur in our region include : 



Townsendia niger Back N. J., but other species of 



the genus southward. 



Laphystia sexfasciata Say N. Y. to Fla., 111., and Tex. 



Echthopoda formosa Loew Mass, to N. C. 



Cyrtopogonfalto Walker Quebec, 111., Fla. 



Cyrtopogon marginalis Loew Canada, N. J., Va. 



Stichopogon argenteus Say On sand, N. J., 111., Calif. 



Lampria rubriventris Macquart. . .Pa., Ga., Tex. 

 Proctacanthus rufus Williston. . . .Mass., N. C., N. Mex. 

 Proctacanthus nigriventris Mac- 

 quart Pa., Carolina. 



1 For the benefit of those interested in the fauna of Plummets Island, 

 Md. ( it may be said that 43 species have been taken upon the island, and 

 25 others in the Great Falls-Little Falls section of the Potomac River valley. 

 Where the data quoted does not make this distribution clear the initials P. I. 

 or V. P. I. (vicinity of Plummers Island) are added. 



- Two species not yet collected are included in the keys. 



3 Johnson, C. W., Ann. Rep. N. J. State Museum. 1909 (1910), pp. 

 749-753. 



4 Johnson, C. W., Bui. Am. Mus. Nat. Hist. 32, Art. Ill, 1913, pp. 60-62. 



