Mar., 1913.] 
83 
Life-Histories of Syrphidae V. 
the lower posterior part. From above, the outline is sub-ovoid, 
broadest in front of the middle, thence narrowing gradually to the 
posterior third; whence the puparium is strongly and unevenly 
compressed to the tip of the respiratory appendage. 
Color at first grayish brown, sometimes marked with oblique 
patches of black; posterior breathing appendage darker. As the 
pupa approaches metamorphosis the anterior end darkens to deep 
reddish-brown in the region of the eyes; while on the posterior 
half, the three principal, yellow abdominal bands of the adult 
become visible through the transparent wall. 
The segmental spines remain, as in the larva, very inconspic¬ 
uous. The posterior breathing appendage also retains its 
characteristics. 
Of three specimens taken on July 7, one pupated July 11, the 
other two the following day. The former emerged as adult July IS, 
the latter two July 20. Hence the duration in the pupal stage 
was 7 to 8 days. I did not determine the place of pupation and so 
cannot say whether, in the field, this stage is passed within the 
galls or not. Examination of a number of the galls later in the 
summer failed to reveal any puparia. 
Adult. 
MaleLength, 11 to 12 111 m. Face and cheeks wholly yellow, 
antenme reddish yellow, the third joint somewhat brownish above! 
but little longer than wide, the arista black. Frontal triangle with 
a small black spot in the middle, gray pollinose along the eyes, 
black pilose in the middle. Dorsum of thorax shining metallic 
green, with light colored pile; lateral margins distinctly yellowish 
pollinose. Scutellum wholly yellow. Abdomen black, the anterior 
half of the black bands sub-opaque, the three principal bands 
very broad, attaining the lateral margins in nearly their full 
width; first band interrupted, the spots narrowly separated, with 
their inner ends rounded; second and third bands with a narrow 
but deep emargination in the middle behind; fifth and sixth seg¬ 
ments with a yellow hind margin. The black forms narrower 
bands than the yellow, and does not quite reach the margin. 
Legs yellow, the tip of hind tibiae and their tarsi brownish. Wings 
hyaline, the stigma yellowish. 
Female: “Front metallic green, yellow below, on the lower 
half with yellowish pollen. Yellow spots of the second abdominal 
segment larger, more nearly square, and only narrowly separated.” 
■—Williston, Synop. N. A. Syrphidae, p. 86. 
