NORTH AMERICAN DIPTERA. 289 



slender abdomen has the third and following segments broadly l)lue- 

 lilack on tlie disk of each, the margins yellowish red, the seventh 

 almost wholly, the hypopygium entirely so. The four front tarsi are 

 also brownish, excei^t the base. 



^iteiiopogon icacidiuus n. sp. 



Male. — Black; abdomen, except base and hypopygium, yellowisli red; wings 

 black ; mystax white. Length 14-1.5 mm. 



Like species of Ospriocerus, but the antennse with a distinct terminal style. 

 Face wholly densely grayish white polliuose, the bri.stles of the mystax white: 

 frontal and occipito-orbital bristles black, beard and long hair of the anterior 

 coxffi white. Dorsum of thorax moderately shining, brownish black, on the sides 

 grayish or browni.sh yellowish pollinose, behind and on the scutellura less thickly 

 so, in the middle with not very noticeable stripes. Abdomen slender, yellowish 

 red, the first, second, and anterior angles of the third segment and the hypo- 

 pygium black. Legs black, the front femora more or less, the front and middle 

 tibife and tarsi pitchy or reddish. Wings black. 



This species has a very different aspect from other Sienopogoiies, 

 but the presence of a well-developed cylindrical antennal style, pre- 

 vents its location among the Ospriocerl. It differs from the known 

 species of Os})rioceri(s also in the possession of long white hair on 

 the anterior coxae. 



Three specimens, Kansas Plains ; taken in a grassy ravine, Aug. 20. 



Sticliopogon trifai^ciatiis Say, Jour. Acad. Phil, iii, 51, 3; Compl. Wr. ii, 

 64 (T)usi/pu(ion) : Thcrevn plngiaia (Harris) Walker, List, etc., i, 223; Dnsypocjon 

 candidus Macquart, Diyit. Exot. ler Suppl. 67, 48 ; Bellardi, Saggio, etc., ii, 78 

 {Stichopogon) ; Dasypogon gnlascens Walker, Trans. Ent. See. N. S. v, 277 [Bel- 

 lardi] ; Dasypogon fasciventris Macquart, Dipt. Exot. 4e Suppl. 69, 75, pi. vi, fig. 

 13 [Bigot]. 



I have compared specimens of this species from New" England, 

 Kansas and Southern California and find no differences. I believe 

 the synonymy above may be safely accepted. 



Triclis tagax Williston, Trans. Am. Ent. Soc. xi, 8. 



A male specimen of this species, received without locality, differs 

 in having the pollinose bands of the abdomen confined to a spot on 

 the hind angles of the segments ; the last two segments red on the 

 hind margins. On each side of the front margin of the dorsum of 

 the thorax there is a large light brown pollinose spot extending back 

 narrowly above the dorso-pleural suture. 



Saropogoii u. sp. 



I have specimens of a species of this genus (California) with widely 

 open fourth posterior cell, of which the abdomen is as slender as that 



TRANS. AMER. KNT. SOC. XIII. (.37) OCTOBER, 1886. 



