134 KANSAS ACADEMY OF SCIEN-CE. 



tempted to pierce my heavy overalls. They will fly in one's face, and bite almost 

 the moment they have alighted. They were also extremely numerous at a swale 

 near the G bar ranch, on the Zuni river. 



Silvivs qnadrivittaUis Say. — I identify numerous specimens from Las Cruces, 

 N. M., as this species. They are all females, taken from June 10 to September 2. 

 My specimens are from 6* to nearly 9 mm. Say's description gives nearly f inch 

 (nearly 10 mm). In some of the specimens the dorsum of the abdomen is more or 

 less tinged with yellowish, but nearly all have the abdomen uniform silvery cinere- 

 ous, except the four longitudinal series of brown spots. Say's description was 

 probably from one or more specimens possessing the yellowish tinge. This species 

 is often very troublesome to horses in the Mesilla valley (vicinity of Las Cruces, 

 Dona Ana county, N. M.) It does not seem to attack man in this locality. It was 

 not met with during a trip through northeastern Arizona the past summer. A 5 

 specimen, which was taken on flowers near Sabinal, N. M., August 7 ( Socorro 

 county), I take to be the S of this species. It differs as follows from the ? : Only 

 two black facial tubercles, the intermediate third one absent; first antennal joint 

 pale fulvous at base; palpi very small, much shorter than in $, very pale fulvous; 

 thorax with a very slight fulvous tinge; abdomen yellowish or orange, more deeply 

 yellow on hind margins of segments, first two segments more silvery; brown mark- 

 ings of abdomen a little heavier; pleurae, sternum and venter less silvery poUinose. 



Apatolestes comastes Williston. — One ? specimen taken at Manguitos Springs, N. 

 M., (Socorro county, near the Arizona line,) June 23, 1 believe belongs to this species. 

 It agrees perfectly with Williston's generic description, and differs from the specific 

 description only as follows: Palpi grayish; tibije brown or blackish. While the first 

 segment and the hind margins of the other segments of the abdomen may be gray- 

 ish or brownish gray, and clothed with sparse whitish hairs, the most of the abdo- 

 men is clothed with black hairs. The length is same — 11 mm.; wing, 9 mm. 



Diachlorus guttatulus n. sp. — Female: Face short, whitish, clothed with pure white 

 hair, without callosities; front quite distinctly convergent anteriorly, yellowish gray 

 poUinose showing more thickly above base of antennae; frontal callosity blackt 

 nearly square, prolonged above in the middle and at each side, the lateral prolonga- 

 tions often cut off, sometimes irregular; an ocellar callosity black, not raised into a 

 tubercle. Antennse inserted well below middle of head, light brownish, annulated 

 portion of third joint black, the third joint at base having no distinct upper angle. 

 Palpi large, almost as long as proboscis, yellowish white, with very few black hairs. 

 Thorax cinereous, with six longitudinal blackish lines, the outermost one on each 

 side less distinct than the others; sternum and pleurro clothed with white hair. Ab- 

 domen silvery gray poUinose, sometimes with more or less of a yellowish-red tinge, 

 especially on the sides of second to fourth segments; first segment with a posterior 

 transverse submarginal narrow brown band, more or less interrupted in the middle; 

 second with an anterior marginal transverse brown band, thickened in middle, but 

 split from behind so as nearly to be interrupted; segments three to five also show- 

 ing an anterior brown margin, at least in middle; segments two to six with four 

 posterior submarginal brown spots, those on fifth and sixth segments usually not 

 quite so distinct, spots rarely coalescing. Wings entirely hyaline, stigma very faintly 

 if at all yellowish; all the posterior cells widely open, anterior branch of third vein 

 with quite a long stump near origin. Legs brownish yellow, front femora slightly 

 darker at tip; front tarsi and tips of front tibias black, tips of other tarsi brownish; 

 front tibiffi slightly enlarged distally. Length, 9 to 10 mm.; of wing, 8 to 9 mm. 

 Described from seven s specimens. Las Cruces, N. M., June 26 to 29. I have referred 

 this to the genus Diachlorus on account of the short face and somewhat swollen 

 front tibia', though the face has no callosities, and the eyes, as revived over wet sand, 



