346 THE BLOWFLIES OF NortH AMERICA 
yellowish golden to brown pollen; vibrissae above oral margin 
by 1.0 and separated by 1.8; palpus 3.5 in length; antennal seg- 
ments orange brown to black, third segment two times as long 
as second; back of head black, with two or three rows of post- 
ocular cilia and with abundant yellowish white hair. 
Thorax black, with thinly silvery pollen, and with shining 
black dorsal longitudinal stripes; fresh specimens with long 
erinkly yellowish brown or golden-yellow (rarely yellowish 
white) pile or hair, this partially or almost totally lacking in 
old or rubbed specimens; pleura lightly to strongly gray polli- 
nose; hindmost preacrostichal and dorsocentral bristles before 
the suture by 2.0 and 1.75, respectively; postalar declivity with 
tuft of long crinkly pile; sclerites at wing-base brownish black; 
mesothoracic spiracle rather small, with bright orange hair; 
mesothoracie spiracle with orange hair; lateral margins of scu- 
tellum with long erinkly pile. ! 
Legs black, pulvilli brownish black. 
Wing hyaline, slightly infuscated with brown basally; costal 
sections 2 to 6 in the proportions 84:45:120:38:6; subcostal 
sclerite orange brown; basicosta black; upper and lower squamal 
lobes orange brown on apical half or more. | 
Abdomen black, thinly covered with silvery pollen, tessellated 
about as in Muscina stabulans, with a shining black middorsal 
longitudinal stripe; fifth sternite (pl. 31, B) as illustrated; all 
sternites and the ventral edges of tergites with yellow pile. 
Genital segments black, first segment with a marginal row of 
about five bristles; second segment smaller, with thin pollen 
and scattered black setae. Internal anatomical features (pl. 31, 
A and C) as illustrated. 
Female. Head width and height 9.6; length at antenna 6.2 ~ 
and at vibrissa 5.4; eye height 6.1; bucca 0.46 eye height; front 
at vertex 0.33 of head width, 0.51 at lunule; outer vertical 
bristles two-thirds as long as inner; frontal row of bristles not 
obsolete above. Otherwise similar to male execept for normal 
sexual differences. , 
Length. 6-12 mm. 
The above description was drawn from North American speci- 
mens which were compared with European specimens determined 
as Pollenia rudis by Brauer and Bergenstamm, and Villeneuve. 
I find no essential differences between them, but Keilin (1915) 
noted that the favored host of Pollenia rudis was Allolobophora 
chlorotica. (Sav.) in Europe; this is not the favored host in 
North America. In both North American and European speci- 
mens the width of the bucca in relation to the eye height varies 
