AMERICAN DIPTERA. 177 



hind femora, except the base and tip, a broad ring on all tibia;, and 

 the tarsi, for the most part black. Wings grayish hyaline." 



Type. — Dr. F. H. Snow states that the type is not at the 

 University of Kansas, although Williston's material is there. 

 Habitat. — Teapa in Tabasco, Mexico (H. H. Smith); N. M. 



Townsendia imlcln'rriina n. sp. 



9- — -Length 3.5 mm. — Head and thorax black; abdomen, except 

 at tip, and the legs, reddish; wings attenuated at base, without allulae, 

 and with but four posterior cells; hal teres creamy white. 



Head black, face narrow, fiat, without gibbosity, pale golden pruin- 

 ose; the mystax white, confined to a thin row of bristles on the oral 

 margin; front as in the typical species, narrow below, extraordinarily 

 widened above, shaped as that of minnta is described to be, brownish 

 pruinose, a spot on either side above the insertion of the antennas and 

 confluent with the margin of the eye, and a much larger patch along 

 the orbits upon the vertex and extending over slightly onto the occiput, 

 silvery white pruinose; ocellar tubercle rather broad, flattened on top 

 and bearing two bristles; on either side of the front above the lower pair 

 of white spots are two black bristles, one situated above the other. 

 Antennae situated a trifle below the center of the head, some longer 

 than the head is high; the basal seginents subequal, the first a trifle 

 longer, the second more robust; the third nearly one and one-half times 

 as long as the basal segments taken together, constricted a little toward 

 the base, enlarged beyond, rather obliquely truncated distally; style 

 very short, distinct, equalling in width the third segment, a trifle more 

 than half as long, and bearing upon its outer distally portion, a small 

 forward directed spine which is nearly concealed by the dense micro- 

 scopic pubescence which covers both the style and the third segment. 

 Proboscis short, polished black. Thorax slightly gibbose in front, 

 thence gradually receding to the scutellum; dorsum and pleurae thinly 

 golden pruinose, on the dorsum showing an indistinct median stripe, 

 and when viewed from above, four shining white spots, one on each 

 humerus, and one on either side above the insertion of the wings; on 

 either side of the dorsum there are two well developed black bristles, 

 one presutural, the other postsutural, and before the former there is 

 a patch of sparse black hair. Scutellum quite large, thick, thinly 

 golden pruinose and fringed with short black bristles. Halteres 

 creamy white; the trichostical bristles sparse and black. Abdomen 

 polished reddish, except the extreme base, last two segments, and the 

 extreme lateral margins of the fifth and sixth segments, which are 

 black; venter reddish, towards the tip, black; the very fine sparse 

 pile of abdomen yellowish; circlet of spines of ovipositor black. Legs, 

 including the coxae, yellowish-red; all the tibiae darkened, almost black- 

 in the middle; the hind pair slightly incrassate at tip; hind tarsi 



TRANS. AM. ENT. SOC, XXXV. (23) MAY, 1909. 



