194 THE BLOWFLIES oF NortTH AMERICA 
dorsocentral bristles four, sometimes only three apparent with 
the second weak (rarely with two or three adventitious bristles 
in the row but the row always spaced for four); under surface 
of scutellum with fine whitish yellow setae. 
Legs black, middle femur with three bristles near middle an- 
teriorly, and four or five basal ventral bristles in row; middle 
tibia with two anterodorsal bristles near middle, one ventral 
bristle near apical fourth; two posterior bristles, one near basal 
fourth and the other near apical fourth, and one posterodorsal 
bristle near apical third; hind femur with anterodorsal, antero- 
ventral and posteroventral rows, and with one dorsal subapical 
bristle; hind tibia with bristles of irregular size, anterodorsal 
row usually represented by two longer bristles, posterodorsal 
row with about five bristles, anteroventral row apically with 
about three bristles, and one dorsal subapical bristle. | 
Wing hyaline, lightly infusecated basally and anteriorly; cos- 
tal sections 2 to 6 in the proportion 70:40:90 :30:2; basicostal 
seale bright orange; third vein setulose from one-third to one- 
half the distance to the cross vein; fourth vein with or without 
an extremely short fold or stump at the angle, bent at about 45 
degrees toward apex of wing; posterior cross vein only slightly 
doubly arcuate; last section of fifth vein one-fifth preceding sec- 
tion; upper and lower squamal lobes infuscated. 
Abdomen metallic bluish green to black, with thin silver pol- 
len; scutellar depression extending four-fifths the distance to 
the hind margin of first tergite; third and fourth tergites each 
with a row of weak marginal bristles; first sternite longer than 
broad, each successive sternite shorter and narrower. 
Genital segments about as described in Apaulina metallica. 
Internal features (pl. 21, G) as illustrated. 
Length. 6-8 mm. 
Distribution. Nearetic: Colorado and New Mexico. 
The type male and the allotype female were reared from pu- 
paria collected in a warbler’s nest in Colorado (M. A. Palmer) ; 
one paratype male was reared from a maggot collected in a spar- 
row or goldfinch nest in Colorado (W. W. Arnold); two males 
and two females were reared from larvae found as subcutaneous 
parasites of a horned lark nestling at Koehler, N. Mex. (Web- 
ster No. 7707, W. R. Walton). 
Walton (1915), in discussing a collection of Apaulina (among 
which was this species), stated, ‘‘This fly was reared from a 
fledgling of horned lark (Otocaris alpestris) by Mr. Wildermuth, 
June 11. The larvae were contained in purulent sores on the 
