18 



interesting', the Califortiian from west of the Sierras and 

 the Nevadan from close up on the eastern slope. 



The vicinity of Stanford University furnishes a wealth 

 of Diptera which I have not seen equalled anywhere in the 

 West. There are ponds, streams, rich woods, pastures, 

 and finally salt marshes, all near by. The richness of the 

 region may be inferred from the large number of new 

 species resulting from the small amount of very superficial 

 work done by me. 



At Claremont and vicinity, in the typical Southern 

 California country, work has just begun. It will be con- 

 tinued with unremitting perseverance in both California 

 and Nevada.* 



MYCETOPHILIDAE. 



1728 Boi^iTOPHiLA HYBRIDA Meig". Stanford University. 



82 Mycetophila obscura Walk Stanford University. This 

 species was abundant about Lagunita in the early spring-. 



1729 Mycetophila trifasciata Coquillet, new species. 



Head black, antennae brown, the base yellow. Mesonotum 

 reddish brown, opaque, the narrow front margin and broad front 

 angles yellow, its short hairs yellow, the lateral bristles brown, 

 pleura black and with a few small yellow spots, pteropleura bearing 

 a row of black bristles, scutellum chiefly yellow. Abdomen black, 

 the genitalia yellow. Legs and halteres yellow, apices of tarsi, of 

 middle and hind coxae and of their tibiae, also apices of hind 

 femora, black; middle and hind tibiae bearing two rows of black 

 bristles on their outer sides, the middle tibiae with two long bristles 

 near the middle of the inner side. Wings hyaline, and marked with 

 three brown cross-bands; the first band begins on the costa and 

 extends into the second basal cell, passing over the small crossvein; 

 a large brownish spot behind the fifth vein appears to represent 

 the continuation of this band; the second band crosses the wing 

 from just before apex of the first vein to apices of forks of the fifth 

 vein, filling the cell formed by these forks, behind which it is 

 abruptly narrowed to about half its previous width; the third band 

 fills the apex of the wing from a short distance beyond apex of first 

 vein to apex of upper branch of fifth vein; the latter vein forks far 

 beyond the forking of the fourth, its forks rather narrowly sepa- 



*A list of the first century of Diptera to be issued in the Inver- 

 tebrata Pacifica series will be published before long, with the first 

 report on Nicaraguan Diptera collected last winter. 



