SuBFAMILY CHRYSOMYINAE 155 
pecially on the margin of ocellar triangle (which is longer than 
in other North American chrysomyine flies), wide at ocellar tri- 
angle but still wider just anterior to foremost ocellus, then nar- 
rowing to narrowest point at lunule; head width 17.0; eye more 
oval than in male. 
Length. 9-11 mm. 
Distribution. Nearetic: The species occurs rather commonly 
from southern Mexico to the state of Washington and as far east 
as Colorado and western Texas. It is most abundant in the far 
Southwest in high altitudes, especially in forested areas, but 
during the winter months specimens may be collected on the 
Pacific Coast in considerable numbers at low altitudes. It is a 
relatively abundant species during the summer in the moun- 
tain ranges of New Mexico, Arizona and California. It occurs 
in the southern portions of the San Jacinto Mountain Range in 
southern California during the winter, but only in high altitudes 
in the summer season. It was not found by the author on the 
Coachella Desert or in Imperial Valley in California, although 
specimens were collected in an arid section east of Yuma, Ariz., 
in November 1950. In southwest Texas specimens may be col- 
lected during the winter, being most abundant in April. 
Specimens of this species are often found in collections under 
the name Cochliomyia macellaria. Many of the specimens of 
Callitroga americana found in the National Museum collection 
had been determined as Chrysomyia wheelert. Superficially, 
americana and wheelert appear similar, since they are of about 
the same size and of much the same coloring. 
Boology, habits and rmmature stages. Paralucilia wheeleri is 
saprophagous like Callitroga macellarva and is of little economic 
importance. Larvae may be found breeding in carcasses, or 
occasionally in myiasis wounds, of animals throughout its range 
of distribution, and generally occur with larvae of Callitroga, 
Phormia, or Lucilia. Breeding takes place under favorable 
temperature conditions in late fall or early spring but is 
probably continuous throughout much of the year in favorable 
situations in southern latitudes. 
Egg. Macrotype, large, hatching in from 20 to 24 hours un- 
der favorable temperature conditions. According to Deonier and 
Knipling (1940), a single egg mass may contain 350 to 500 eggs. 
Larva. Of typical calliphorine shape and habitus. With a 
mean temperature of 69.5° F. the larva matures in approximate- 
ly five days. Deonier and Knipling (1940) state that this period 
is increased with a decrease of temperature; at 58.5° F., for in- 
stance, 10 days are required to complete development. Mod- 
