502 PROCEEDINGS OF THE NATIONAL MUSEUM VOL, 118 
Abdomen yellow, with tergites darkened along the posterior mar- 
gins; tergites often more extensively darkened, at least in dried 
specimens. 
FEMALE.—Similar to the male, except no claw on anterior basi- 
tarsus, femora only slightly thickened, and no brushlike hairs on the 
midcoxae. 
LenoetH.—4.5—6.0 mm. 
Distripution.—Alaska, across Canada and northern United States 
to Newfoundland, south to California, Utah, Colorado, Tennessee; 
April—October. 
ReMArKS.—Garrett was apparently the first to recognize that this 
North American species is distinct from the European Swillia bicolor 
(Zetterstedt). In his original description Garrett pointed out the 
very conspicuous difference in the male terminalia. He also indicated 
that the wing veins of S. loewi Garrett are dark, rather than yellowish, 
but I have found this character to be variable in both S. loewi Garrett 
and S. bicolor (Zetterstedt). The brushlike matted hairs of the mid- 
coxae of S. loewi Garrett are not prominent in S. bicolor (Zetterstedt). 
The terminalia are compared in figures 1 and 2. 
Suillia imbata (Thomson) 
FIGURE 3 
Helomyza limbata Thomson, 1868, p. 569.—Aldrich and Darlington, 1908, p. 91. 
Suillia limbata (Thomson), Czerny, 1924, p. 41. 
The relatively narrow cheek (cheek-eye ratio 0.25 or less) is a dis- 
tinguishing character of Suillia quinquepunctata (Say), S. sororcula 
Czerny and S. limbata (Thomson). Of these, only S. limbata (Thom- 
son) has the eye round in lateral view. 
MALE AND FEMALE.—Back of head, ocellar triangle, and frontal plates 
yellow to reddish orange, often with a grayish pollinosity; front yel- 
lowish orange; face, cheeks, and proboscis yellow; antennae yellowish 
orange, the aristae dark brown to black; aristae plumose; oral vibrissae 
strong, buccal setae in 2 to 3 irregular rows; orbito-antennal spot 
absent; eye round; cheek-eye ratio 0.25 or slightly less. 
Thorax with dorsum reddish orange; pleura usually lighter than 
dorsum; scutellum with setae or hairs confined to a small number 
(usually 1 to 3) on the lateral edge between the bristles; pleura bare 
except for sternopleuron, which has the usual strong bristle near the 
upper edge with several setae near it and longer hairs ventrally be- 
tween the coxae. 
Legs yellowish orange, becoming darker distally; forefemora with 
the usual posterodorsal and posteroventral rows of bristles; mid- 
