DIPTEROUS PARASITES. 1917 



Acroglossa hesperidarum Harris, MSS. PI. 89, figs. 21, 26. 



Mule, female. — Frout ^vitll a golden yellowish cast ; face silvery white, the ground- 

 color on the oral margin yellow. Antennae black, the first two joints and immediate 

 base of the third yellowish red. Palpi reddish yellow ; proboscis black. Mesonotum 

 thinly polUnose, with four, rather broad, shining black stripes. Scutellum broadly 

 reddish yellow. Abdomen black, with a broad, variable, gray, poUinose band on each 

 segment ; extreme tip red. Legs black. Wings grayish hyaline. Length, 11-12 mm. 



Two specimens, from the Boston Society of Natural History, labelled, 

 apparently by Harris, "293, N. H.," and bred by him from Epargyreus 

 tityrus. The sides of the face in the male are scarcely a half the width of 

 the median depression ; in the female they are three-fonrths or more as 

 wide, the depression being smaller, and the sides wider. This, or an allied 

 species, is not rare in collections. 



Exorista futilis Say. PI. 86, fig. 10. 



Tachina (Exorista) futilis (Say) Osten Sacken, Canadian Entomologist, xix: 161 (1887). 



JIale, female. — "Bottom of the antennal foveae silvery gray; the lower part of the 

 cheeks likewise ; lateral part of the face and the orbit of the eyes below and behind 

 (genal and occipital orbit) brassy-yellowish, the coloring of the front being of a more 

 saturate yellow than the lateral parts of the face; above the antennae, in the middle 

 of the front, a brown stripe, attenuated posteriorly; it bifurcates on the vertex, en- 

 closing the grayish, ocellar triangle; the hind plane of the head (occiput) gray. 

 The row of frontal bristles consists : first, of three bristles pointing backwards, 

 the uppermost of which is placed on the top of the vertex; second, of three 

 shorter bristles pointing forward ; third, of four or five bristles, which form diverging 

 rows, descending on each side of the antennae, the last being a little below the end of 

 the second antennal joint. Between the frontal bristles and the eyes, the front bears 

 numerous little hairs; between these rows, on the ocellar triangle is the usual pair of 

 bristles pointing forwards. The females have three supernumerary pairs of larger 

 bristles, the first is placed behind the upper corner of the eye, the other two between 

 the frontal row and the orbit of the eye. Among the above described smaller hairs, 

 immediately below the last bristle, the brassy yellow color of the face shows a brown, 

 changing spot, visible in an oblique light only ; below this place, the lateral parts of 

 the face are smooth ; a short distance above the oral margin there is, on each side, the 

 usual long bristle; above it, some shorter hairs reach to about one-quarter of the dis- 

 tance between the long bristle and the root of the antennae. Antennae black; second 

 joint with grayish pollen, and with a crest of short, stifl' bristles ; third joint long, with 

 parallel sides, more than three times the length of the second, not quite reaching the 

 edge of the mouth. Eyes distinctly pubescent. Ground color of the thorax bluish- 

 black, almost concealed by five stripes of gray pollen, with intermediate black lines; 

 the gray stripes are especially apparent when viewed obliquely from the posterior end 

 of the body; in this light the median stripe appears bifurcated posteriorly; the next 

 pair abbreviated posteriorly ; the lateral pair very broad anteriorly, over the humeri. 

 Scutellum bluish-black, with gray polUnose reflections ; its tip faintly brownish [or 

 red] ; on the hind edge there are six [or eight] bristles, the intermediate [apical] pair the 

 shortest; above this pair, on the plane of the scutellum, another similar pair. Pleurae 

 grayish polUnose. Abdomen black, marmorate with silvery gray ; the fourth segment 

 brassy yellow [poUinose]. The whole abdomen is covered with dense, short hairs; a 

 pair of longer bristles near the hind margin of the first and second segments; a row 

 of such bristles on the hind margin of the third segment, and a double row at the end 

 of the fourth. Legs black; pulvilli brown; knees slightly brownish. Wings: the 

 first posterior cell open (closed by the prolongation of the costal vein, however, which 



