60 Annals Entomological Society of America [Vol. VI, 



32 Neurigona minuta n. sp. 



Dark metallic green; arista white; hind coxte with a yellow bristle 

 on the outside. Length 2 mm. 



Female: Face, front and occiput greenish black, with but little 

 pollen (at least in the type specimen) ; palpi and proboscis yellow, the 

 former with minute black hairs on the surface and a black bristle at tip ; 

 antennae dark reddish brown, the third joint rounded, hardly pointed, 

 and more brown than the basal joints, the arista inserted near the apex, 

 white. Thorax rather dark metallic green, covered with gray pollen; 

 humeri with only a trace of yellowish; the flattened space before the 

 scutellum not very sharply defined; bristles of the thorax strong, acros- 

 tichal bristles well developed, in two rows; the outer pair of scutellar 

 bristles minute but distinct. Abdomen dark metallic green, with black 

 hairs; venter dark. Legs and coxae pale yellow; front coxas with whitish 

 hairs and bristles ; middle coxas with brownish hairs ; the large bristle on 

 the outer surface of the hind cox« yellow; the hairs on all the legs very 

 minute; front and middle tarsi about one and one-half times as long as 

 their tibise, their first joint being about half as long as the tibise; middle 

 tibias with two black bristles near the base, one on the front side, and 

 one on the outer side ; hind tibias with a row of four or five black bristles 

 on the posterior surface; hind tarsi a little longer than their tibise, and 

 with the first joint only half as long as the second. Halters, tegulae and 

 their cilia pale yellow. Wings hyaline, only slightly tinged with grayish; 

 venation about as in N. aldrichii (Fig. 12), except that the posterior 

 cross-vein is only its own length from the wing margin measured on 

 the fifth vein, and the apical half of the last section of the fourth vein is 

 nearly straight; veins brown, becoming pale yellow at the root of the 

 wing. 



Described from one female from Philadelphia, Pa., which 

 was bred from decaying oak, May 23, 1907. Type in the 

 collection of Prof. J. M. Aldrich. 



Note. — This is the smallest species of the genus that I have 

 seen, and is very distinct from all the others. It can readily 

 be distinguished by the pale bristles of the coxae, and its white 

 arista. 



