J. M. ALDRICH. 279 



pi(iii.<>poi>i:viJS. 



Bigot, Annales Soc. Eut. France, 269, 1890. 

 Aldrich, Canad. Ent., Aug., 1904, 246. 



The genus is represeuted in America by a large number of spe- 

 cies, especially in the warmer regions. Many were described by the 

 early writers without mentioning the essential characters. When I 

 came to work u[) the Mexican and Central American Dolicliopodi- 

 dse for Biologia Centeali-Americana, I found it necessary to under- 

 take a thorough study of all the American sj^ecies, so far as they 

 could be made out from the rich material furnished me, my own col- 

 lection, and the descriptions. The results, as far as they pertain to 

 the fauna in that work, will be found in Biologia, Diptera, I Suppl., 

 350-364, where twenty- three new species are described, and a table 

 of species given, the old name ]*si/opas being used. 



I find my.self with a considerable residuum on hand, consisting of 

 four new North American and two South American species, which 

 for the sake of completeness I mentioned in my table, but could not 

 publish at that time on account of their being extra limital. The 

 descriptions are given herewith, preceded by a table of the American 

 species known to me {pilosits is the only exception — I have not 

 seen it). 



TABLE OF MALE SPECIES. 



1. Femora black 2. 



Femora yellow 35. 



2. Wings with dark markings 3. 



Wings without dark markings 22. 



3. Fore tarsi with dense black fringe on sides of 4th and .5th joints, middle tarsi 



with 2ud and 3d joints less broadly fringed (Mex.). 



bifiinbi'ialus Aldrich. 

 Fore tarsi of different structure. ... 4. 



4. Fore tibiae black 5. 



Fore tibise pale, at most somewhat brownish 9. 



5. Face with numerous, delicate, pale hairs (U. S.) patibiilatiiw Say. 



Face destitute of pale hairs 6. 



6. Second joint of autennse with many very long biistles 7. 



Second joint of anteunsB with few and short bristles 8. 



7. Last four joints of fore tarsus short, subequal (West. U. S.). 



I>ilicoruis« n. sp. 

 These joints of gradually decreasing length (West. U. S., Mex.). 



inelainpus Loew. 



8. The brown crossbands broadly connected on'the fourth vein, leaving a round 



hyaline drop in the first posterior cell (Brazil). 



;;iitt'Ula Wiedemann. 



Crossbands not connected behind ; 5th joint of fore tarsus slightly compressed, 



with silvery reflection on inner side (Mex.). . .prsestaiis Aldrich. 



TRANS. AM. ENT. SOC. XXX. OCTOBER. 1904. 



