162 Proceedings of the Biological Society of Washington. 



as long as head; segment 1 lighter in color than head; 2 concolorons 

 with head; 3 pale brownish yellow; 4 distinctly darker ; 5-7 blackish 

 brown. Prothorax about 1.2 times as long as head and nearly 1.5 times 

 as wide as long; two long bristles at posterior angles, and between them 

 three pairs of much shorter ones ; notnm spinose, with two bare areas. 

 Legs blackish brown, with inner surfaces of fore tibia?, both ends of mid- 

 dle and hind tibia?, and all tarsi, yellow. Wings of fore pair dark grayish 

 brown, nearly white in basal fourth ; principal vein with three nearly 

 equidistant bristles in apical half. 



Measurements of holotype. — Length 1.27 mm.; head, length .120 mm., 

 width, .157 mm.; prothorax, length .144 mm., width .212 mm.; meso- 

 thorax, width .300 mm. ; abdomen, width .324 mm. Antennal seg- 

 ments: 1, 24m; 2, 40m; 3, 58m; 4, 51m; 5, 41m; 6, 54m; 7, 21m; total 

 length of antenna, .29 mm. ; width at segment 4, .022. 



Described from seventeen females as follows: Plummer's Island, Mary- 

 land, March 30 and April 6, 1913, in flowers of Muscari racemosum and 

 Erythronium sp., W. L. McAfee and J. D. Hood, 11 females; Havana, 

 Illinois, June 19, Unit, in flowers of clematis viorna, C. A. Hart, 6 

 female-. 



Type locality. — Plummer's Island, Maryland. 



Zygothrips harti sp. nov. 



Female, macropterous. — Color fuscous to nearly black. Head about 1.2 

 times as long as wide; cheeks almost perfectly parallel, smooth; eyes 

 slightly less than one-third as long as head; posterior ocelli in front of 

 middle of eyes; postocular bristles capitate, three-fourths as long as eyes. 

 Antenna' 1.7 times as long as head, nearly uniform dark blackish brown; 

 segment 1 with base pale; 2 pale in outer apical half; 3 pale, darkened 

 with brown along inner surface, indistinctly banded across apex and 

 beyond pedicel; 4-N blackish brown. 4 and 5 often pale at middle and 

 toward outer surface; segment 7 nut broadly united to 8, the latter sub - 

 conical, slender, and nearly three times as limy as wide. Prothorax about 

 .7 as long as head and (inclusive of coxae) about twice as wide as long; 

 one pair of bristles at anterior angles and two at posterior angles, about 

 as prominent as the postoculars and either blunt or capitate ; midlaterals 

 and anterior marginals minute. 1'ore tarsi unarmed. Wings slender, 

 narrowed at middle, sparsely fringed and without interlocated subapical 

 hairs; fore wings with a small spot of brown at base. Tube a little more 

 than half as long as head, 1.7 times as long as basal width, and a little 

 more than half as wide at apex as at base; terminal bristles twice as lout; 

 as tube. 



Measurements of holotype. — Length 1.09 mm.; head, length ,156 mm. 

 width .125 mm.; prothorax, length .107 nun., width (inclusive oi 

 coxa 1 ) .204 mm.; pterothorax, width .209nnn.; abdomen, width 

 .240 mm.; tube, length .084 mm., width at base .051 mm., at apex 

 .027 mm. Antennal segments: 1,25m; 2, 36m; 3,35m; 4,33m; 5, 12m; 



