390 ERNEST A. BACK. 



each side; the last segment with red on the hind border, and more 

 slightly so on each side border. (I believe that Walker has counted 

 the first two segments of the abdomen as four; the seventh and eighth 

 in this description really refer to the fifth and sixth.) Legs red, 

 clothed with short tawny hairs, hips black; tibiae beset with some 

 longer tawny hairs; feet pitchy, and armed with bristles; hind tibia: 

 slightly curved and club-shaped; hind tarsi rather broad. Wings nar- 

 row, slightly gray; each with two large brown spots, one on the middle 

 of the fore-border, the other at the tip of the wing, and they descend 

 into the disk along the borders of the cross-veins, the hind border 

 about the tip is brownish-gray, with a colorless streak on each areolet; 

 wing- ribs and veins black; poisers tawny. Length of body 4^ lines; 

 of wings, 9 lines." 



Type. — M. C. Z. (pictus). That of Dasypogon amastris is at 

 the British Museum. 



Habitat. — N. J. (Smith Cat.) ; D. C. (type, pictus) ; Ga. (type, 

 amastris); St. Augustine, Fla. (C. W. Johnson). 



According to Prof. Johnson, this is a fall species. He has 

 taken it in Georgia in October. The male wing is much as 

 in dives and (Emulator. Legs almost wholly reddish, but the 

 tarsi darker toward the tip. The female has a velvety black 

 stripe on the thoracic dorsum divided by a distinct, rather 

 golden pruinose stripe. This is less distinct in the male and 

 female of dives and csm-ulator. 



Xioocles politiis. 



Dasypogon politus Say, Jour. Acad. Sci. Phil., Ill, 52, 1822; 

 Compl. Works, II, 65. 



Dasypogon politus Wiedemann, Auss. Zw., I, 405, 1S28. 



Dasypogon politus Walker, List. VI, 421, 1854. 



Pygostolus argentifer Loew, Cent., VII, 28, 1866. 

 % 9- — Length 8-10 mm. — Black; fifth and sixth abdominal seg- 

 ments silvery- white pruinose; tibise and tarsis usually reddish; wings 

 hyaline on basal third, the outer two-thirds darkened in various de- 

 grees. Female like male, only the abdomen is normal and the lateral 

 margins of all the segments are whitish pruinose, the fifth and sixth 

 segments without the silvery bloom found in the male. Atlantic 

 States species, usually appearing in the spring of the year. 



%, . — Face grayish pruinose, the front brown; the fine bristles of 

 the mystax on the oral margin yellowish-brown, the pile higher up on 

 the face and the beard, very fine and white; hair of ocellar tubercle 

 and the occipito-orbital bristles yellowish. Antennae black, the third 

 segment sometimes with a reddish tinge; the first segment slightly 

 longer than the second; the third not quite twice as long as the first 



