CLASSIFICATION. 



By M. C. VAN DUZEE. 



TABLE OF THE NORTH AMERICAN SPECIES OF DOLICHOPUS. 



MALES (for females, see p. 26). 



Division into Groups. 



A^ Femora largely black, at least one pair mainly black. 

 B^ Infra-orbital cilia black. 



C^. Cilia of calypters pale Group A. 



C^. Cilia of calypters black Group B. 



W. Infra-orbital cilia pale. 



C. Middle tibiae black Group C. 



C^. Middle tibiae yellow Group D. 



A^. Femora yellow, at most the tips of the hind ones black. 



B'. Infra-orbital cilia black Group E. 



W. Infra-orbital cilia pale. 



C^ Cilia of the calypters pale Group F. 



C^. Cilia of the calypters blacl* 



D^ Hind tibae distinctly black at tip Group G. 



D2. Hind tibiae not or but slightly infuscated at tip. 



E^ Hind tarsi wholly black Group H. 



W. Hind tarsi distinctly yellow at base Group I. 



Group A. 



Hind tibiae yellow, with sharply defined black tip; costa without distinct enlarge- 

 ment at tip of first vein No. 58, laticornis Loew. 



Hind tibiae largely infuscated, the black not sharply defined; costa -with a small but 

 distinct enlargement at tip of first vein No. 59, nodipennis, new species. 



Group B. 



1. Anterior basi tarsi with a row of erect bristles below (Indiana). 



No. 49, retinens, new species. 

 Anterior tarsi without such bristles 2. 



2. Middle femora at least half yellow, or yellowish 3. 



None of the femora with more than apical third yellow 12. 



3. Middle femora black at base, gradually becoming yellow, but largely black- 



ish; lamellae small and infuscated 4. 



Middle femora wholly yellow, or with the black more distinctly limited 5. 



4. Third and fourth veins of the mng quite close together at their tips, ap- 



proaching each other beyond the bend in fourth (Wisconsin). 



No. 57, umbrosus, new species. 

 Third and fourth veins well separated at their tips, nearly parallel beyond 



the bend (New York) No. 55, adultus, new species. 



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