168 THE BLOWFLIES oF NortH AMERICA 
a very small percentage of the total blowfly population during 
the summer months except at high altitudes and in northern 
areas. Adults may be collected rather frequently in early fall 
months, and they hibernate when temperatures drop too low 
for adult activity. Hibernating adults may be found in numbers 
in tunnels of various wood-boring insects. A few adults may 
be collected upon the sunny side of buildings on warm days dur- 
ing winter months. Females will not oviposit at this season of 
the year. | 
The preoviposition period ranges from 7 to 17 days, according 
to Bishopp (1915, p. 327). 
Adults of Phormia regina will migrate as far as 11 miles in 
less than 48 hours, according to Bishopp and Laake (1921, p. 
765). Spermatogenesis and fertility of regina were studied by 
Cowan (1932), and its olfactory responses by MeIndoo (1933). 
Economic wmportance. Phormia regina is a well-adapted fac- 
ultative saprophagous species capable of causing wound myiasis 
and serious injuries to man and domestic animals under certain 
environmental conditions. It appears to be of especial impor- 
tance where soiled wool, or other factors not necessarily associa- 
ted with wounds, render sheep or other animals particularly sus- 
ceptible to its attack. It is also found commonly in wounds 
caused by castration and dehorning, such wounds occurring 
most frequently from November to March in southern states 
and during early spring or late fall in the Middle West. Parish 
and Laake (1935) state that during the spring months this 
species constituted 67 percent of all adults reared from larvae 
which developed in wounds of domestic animals in the Menard 
area of Texas. They concluded that it is of more importance 
than Callitroga americana until as late in the season as May 14. 
Knipling and Rainwater (1937) found regina to be the most im- 
portant ‘‘secondary’’ myilasis-producing blowfly in southeastern 
United States. 
Larvae of regina have been used in postoperative surgery, and 
methods for the rearing of sterile maggots of this species are 
given by Haub and Miller (1932) and Robinson (1933). 
When fresh blood is present in abattoirs, regina often becomes 
extremely abundant and annoying. 
BOREELLUS ALDRICH AND SHANNON 
Boreellus Aldrich and Shannon, Insecutor Inscitiae Menstruus. 
11:107, 1928; Enderlein, Gesell. f. naturf. Freunde Sitzber. 
4-7 :245, 1935; Townsend, Rev. de Ent. 1:71, 1931; Manual 
of Myiology, vol. 5, p. 139, 1987. Genotype, (Boreéllus aris- 
