Vol. 5, p. 125-127. July 21, 1924. 



Occasional Papers 



OF THE 



Boston Society of Natural History. 



NEW ROBBER-FLIES (ASILIDAE, DIPTERA). 1 

 BY STANLEY W. BROMLEY. 



The numerous papers that have appeared recently on this 

 family of flies might lead one to believe that the field was nearly 

 exhausted in this country, so far as new species are concerned. 

 It is a significant fact, however, to which attention was called by 

 Melander in the December (1923) number of Psyche, in reference 

 to the coincidence of his study of the genus Cyrtopogon with 

 that of Curran's review of the genus, that nineteen new species 

 in such a well-known genus should be described by two inde- 

 pendent workers without synonymy. I believe that in both 

 Cyrtopogon and Dioctria there will be found undescribed species 

 in unworked collections, and more intensive collecting will bring 

 to light many more. 



Dioctria propinqua, new species. 



9 . — Length 11 mm. Black. Face and anterior vertex, golden pruinose. 

 Antennae, black with golden hairs; third segment slightly longer than 1 and 

 2 combined; style small. Proboscis black; palpi black with yellow hair. 

 Beard white. Occiput very pale yellow pollinose. Thorax, abdomen, coxae, 

 femora, tarsi and distal half of tibiae black. Proximal half of tibiae pale 

 brown. Coxae with white pile; legs with scattered golden hairs. Thoracic 

 dorsum golden pollinose with vestiture yellow. Hypopleurae and a patch 

 anterior to the mesopleural suture silver pollinose becoming golden toward 

 base of wings. Wings smoky; veins yellow basally, becoming brown distally. 

 Abdomen with very short, scattered, appressed golden pile, becoming more nu- 

 merous posteriorly, longer and lighter in color on venter and first three tergites. 



Holotype from Dorchester, Massachusetts (June). In Me- 

 lander's key to this genus (Psyche, vol. 30, p. 213, December, 

 1923), it would run to No. 9, sackeni, form rivalis Melander. 

 It differs, however, in having the wings lighter-colored, in having 

 the proximal half of the tibiae very pale brown rather than black, 

 and in being appreciably greater in length. At any rate, the 

 specimen is sufficiently distinct from sackeni to merit description. 

 The holotype is in the collection of the Boston Society of Natural 

 History. 



Dioctria seminole, new species. 



9 . — Length 8 mm. Black and yellow; a slender species. Vertex, palpi, 

 antennae, black. Style very small, slightly less than one-sixth the length 



1 Contribution from the Entomological Laboratory of the Massachusetts 

 Agricultural College, Amherst, Massachusetts. 



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