298 Professor Williston on the 



DIXID^. 



DiXA. 



Meigen, Syst. Beschr., i., 216, 1818. 



1. Dixa clavnlns, n. sp. (PI. X., fig. 73, wing.) 



$. Head black, lightly greyish-pruinose ; palpi aud rostrum a 

 little reddish. Antenna3 black, the basal joints somewhat reddish. 

 Thorax yellow, the mesonotum with three dark-brown stripes, the 

 median one abbreviated posteriorly, and divided by a slender line ; 

 the lateral ones begin a little before the termination of the median 

 one. Scutellum and mesonotum brownish-yellow. Abdomen dark- 

 brown. Legs brown oi- yellowish brown : the tip of the hind 

 tibiae and their tarsi blackish ; the femora, for the greater part, 

 yellowish ; hind tibite thickened at the tip. Length of body 2 mm., 

 of wings 3 mm. 



Four s])ecimens. This species must be closely allied 

 to D. clavata, Loew, from Massachusetts, and I was, at 

 first, inclined to identify it with it. It differs from the 

 description, however, in several important points. The 

 pleur«3 are immaculate yellowish, the legs are darker 

 coloured, and the wings are uniformly tinged with 

 brownish, not hyaline, with markings. 



RHYPHID^. 



RHYrHUS. 



Latreille, Nat. Hist., etc., xiv., 291, 1801. 



1. Rhyphus dolorosus, n. sp. (PI. X., fig. 74, wing.) 



5 . Front and occiput black, somewhat greyish-pruinose. 

 Mesonotum yellow with three brown stripes ; wings broadly 

 clouded on the distal and posterior margin, with two conspicuous 

 brown spots in front, and narrow brown clouds on the cross-vein;. 

 Length of body 4 mm., of the wings 5 mm. 



Fio.it a little narrower below, the ocelli situated wholly in front 

 of a line drawn through the angles of the eyes. Face more 

 yellowish. Eyes reaching to the oral margin below. Palpi and 

 proboscis black. Antennfe black, the two basal joints j'ellowish. 

 Mesonotum opaque yellow with three brown or brownish-red 

 stripes, the middle one abbreviated posteriorly the lateral ones in 



