NO. 1202. GENERA OF THE ENCYIITINJS—ASHMEAD. 349 



fifth and sixth also elongate, but shorter, than the fourth; club fusi- 

 form, indistiuctly 3-joiiited. Mesoiiotum subdepressed in front of the 

 scutellum; asilliB not quite uieetiug at base of scutellum; metathorax 

 short, with the hind angles smooth, bare. Wings hyaline, the venation 

 mostly dark-brown or piceous, the submarginal vein, except at apex, 

 pale yellowish; marginal vein about thrice as long as the stigmal, the 

 postmarginal short, not longer than the stigmal, the latter being short, 

 subpetiolate and ending in a knob. Legs aeneous black, the hind 

 coxffi metallic green, the tarsi brown-black or fuscous, the anterior and 

 middle tarsi basally and the middle tibial spur, yellowish. 



Types.— G2ii. Nos. 5082-50S5, U.S.KM. (Carl F. Baker collection.) 



Hahitat. — Colorado. 



3. MEROMYZOBIA Ashixiead, new genus. 

 (Type, Ericydnus mavulipeiinis Asbniead.') 



Stature and general appearance of Ericydnus Walker, but readily 

 distinguished from it and allied genera by its antennal characters, the 

 funicle being only 4-jointed, with two small ring-joints. It is the only 

 genus in the tribe Ectromini with two ring-joints, and includes wingless 

 or subapterous forms, as well as those with wings fully developed. 



Head transverse, viewed from in front rounded, the frons subconvex, 

 finely shagreened or coriaceous, with a few minute punctures scattered 

 over the surface. Mandibles bidentate. Antennse 11-jointed — scape, 

 pedicel, two ring-joints, a 4-jointed funicle, and a 3-jointed club. Prono- 

 tum conical, the hind margin obtusely triangularly eujarginate; meso- 

 notum smooth, a little wider than long; scutellum about two-thirds the 

 length of the mesonotum, with the axillae, touching each other at their 

 inner basal angles; metathorax short, about one- third the length of the 

 scutellum, smooth. Winged form with the wings hyaline, but banded, 

 or at least maculate with fuscous; the marginal vein is somewhat long, 

 linear; the stigmal is always shorter than the marginal and issues 

 obliquely at an angle of less than 30 degrees; the i)ostmarginal vein is 

 a little longer than the stigmal, but shorter than the marginal. Abdo- 

 men conic-ovate, and usually a little longer than the thorax. 



The species in this genus, whose parasitism is known, destroy Dip- 

 terous larvae belonging to the genus Meromyza. The following are the 

 sj)ecies of our fauna : 



1. MEROMYZOBIA AMERICANA Ashmead. 



Prionomastix americana Ashmead, Ent. Amer., IV, 1888, p. 16, lu ale. — Dalla 

 Torre Cat. Hym., V, 1898, p. 265. 



Ty2}e.— Gat. No. 4719, U.S.N.M. (Ashmead collection.) 

 Hahitat. — Florida. 



2. MEROMYZOBIA BIFASCIATA Ashmead. 



Homalotylus iifasciatus Ashmead, Bull. No. 1, Colo. Biol. Assoc, 1890, p. 28, fe- 

 male.— Dalla Torre Cat. Hym., V, 1898, p. 246. 



