500 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 4.;. 



slightly longer in female, first division more than twice as long as 

 other two together, second and third divisions subeqiial, third vein 

 distinctly thickened at tip, fourth vein hardly bent at base and 

 slightly recurved at tip, ending distinctly in front of wing tip; hal- 

 teres yellow. 



Length, 1-U mm. 



I have only seen a single specimen that I believe is identical with 

 this European species. 



Locality. — Colorado (collection of Coquiilett). Brues records it in 

 his paper on the famih' from Idaho, California, and Texas. 



Genus MELALONCHA Brues. 



This genus is represented by a single species, pulchella Brues, from 

 Songa, Bolivia, South America. Resembles in appearance the 

 species in Apocephalus Coquiilett, but easily distinguished by the 

 characters given in generic table. I have not seen the species, 

 which is unrepresented in the collection here. It has also been 

 recorded from Paraguay by Brues. 



Genus GYMNOPHORA Macquart. 



Represented by a single species in North America, which is iden- 

 tified with arcuata Meigen, the one commonly met with in Europe. 

 Another species is met with in Paraguay, which is close to arcuata 

 Meigen, in appearance. Brues described this South American species^ 

 under the specific name colona. This latter species differs from 

 arcuata in having the frontal bristles more distinct and in having 

 black halteres. 



Localities of specimens in National Museum collection belonging to 

 arcuata Meigen: White Mountains, New Hampshire (Morrison); 

 Victoria, Texas (E. A. Schwarz); Woodside, Maryland (J. E. Bene- 

 dict, jr.) ; Mount Washington, New Hampshire (Mrs. A. T. Slosson) ; 

 Lawrence, Kansas. 



The South American species is unrepresented in collection. 



Genus PLASTOPHORA Brues. 



TABLE or SPECIES. 



1. Larger species; frons as wide as high, proboscis enlarged, as long as height of head, 



chitinous; length, 1.75 mm beime, p. 501. 



Small species, 1 mm. or less 2. 



2. Species about ^ mm. in length, costa to about middle of wing, thorax grayish, 



hind tibia bare, the middle pair of bristles in second row very close together 

 and higher placed than the outer pair which are very close to eye margin. 



formicarum, p. 501. 

 Species 1 mm. in length, costa distinctly short of wing, thorax yellow or brown. . .3. 



1 Ann. Nat. Mus. Hungary, vol. 9, 1911. 



