J. K. MALLOCH 141 



men narrowly ovate; hypopygium small; first sternite bare; fifth deeply cleft, 

 with a group of bristles on a slightly elevated area just caudad of inner ex- 

 tremity of cleft, two or three of the bristles very strong. Fore tibia unarmed; 

 mid tibia with three posterior bristles; hind femur with five or six bristles 

 on apical half of antero-ventral surface; hind tibia with two antero-ventral 

 and two antero-dorsal bristles. Outer cross-vein bent in middle; veins three 

 and four divergent at apices. Length, 5.25 mm. 



Type. — cf ; Bozenum, Montana, July 17, IDIU, [IllinoisJ. 



Helina johnsoni sp. n. 



Male. — Black, subopaque, covered with den.se yellowish pruinescence. 

 Head black, orbits, face, and cheeks with dense silvery pruinescence; second 

 antennal joint brown, its apex and the base of third rufous, remainder of 

 third joint black; jialj)! brownish black, paler at base. Thorax rather indis- 

 tinctly quadrivittate. Abdomen with two pairs of faint black dorsal spots. 

 Legs rufous yellow, all coxae grayish, tarsi fuscous. Wings clear, veins 

 yellowish, noticeably so at bases; both cross-veins consjncuously but not 

 broadly infuscated. Calyptrae pale yellow. Halteres yellow. 



Eyes with distinct but not dense hairs, separated at narrowest jiart of 

 frons by a distance about equal to width across posterior ocelli; frons pro- 

 tuberant at base of antennae, where the parafacnal is very distinctly wider 

 than third antennal joint; cheek about twice as high as width of parafacial; 

 arista with the longest hairs at least as long as width of third antennal joint. 

 Thorax with four pairs of postsutural dorso-central bristles, and without 

 strong presutural acrostichals; prealar bristle very small; lower anterior 

 sternopleural bristle of moderate length, much longer than in female; hypo- 

 pleura bare. Abdomen short-ovate; first sternite bare, fifth with a large 

 rounded posterior excavation, the surface bristles of moderate length and 

 slender. Yove tibia with a posterior median bristle; mid tibia with three or 

 four posterior bristles in an irregular series; mid femur with two strong bristles 

 near base on posterior surface; hind femur with about six bristles on apical 

 lialf of antero-ventral surface, and three or four at apex on postero-ventral ; 

 hind tibia with eight or more antero-ventral, two antero-dorsal, and about 

 ten posterior bristles. Costal thorn small; outer cross- vein curved in middle; 

 veins three and four decidedly divergent at apices. 



Fciiinlc. — .Similar to the male in color. The head is grayish pruinescent, 

 and the abdomen has rather indistinct tlorsal checkerings. 



Eyes sejxirated by a little over one-third of the head-width at vertex, and 

 over one-third at base of antennae. Hind tibia with four or five antero- 

 ventral and two antero-dorsal bristles. One costal thorn much longer than 

 in male. Length, 7.5 to S.5 mm. 



Type. — o^; Brookline, Massachusetts, June 18, (C. W. John- 

 son), [B. S. N. H.]. Allotype. — 9; Wootll)ury, New Jersey, 

 June 7, 1896, (C. W. Johnson). Paratypes. — 1 cf , Provincetown, 

 Massachusetts, June 29, 1891; 1 9, Auburnclale, Massachusetts, 



TRANS. .\M. ENT. SOC, XLVI. 



