ENTOMOLOGY

PHASES IN THE LIFE HISTORY OF NON-BITING FLIES 131These flies are necrophagous and deposit their eggs upon any fresh,decaying or cooked meat, and upon dead insects; they breed occasionallyin human excrement and sometimes will deposit their eggs in open fleshwounds. On the battle fronts of Europe and Asia where the wounded layfor long periods and whero many dead bodies remained uncared for, theseflies multiplied to tremendous numbers and were largely responsible forthe carrying of infections to wounds. When a fly lays its eggs in livingflesh and the larvre develop therein, the iI\fection is called myiasis. Thissubject is of such importance th!1t two entire lectures is devoted to it(Chapters XII and XIII).Impottant as they are, the blow flies are usually subordinated tothe house fly in the discussion of dangerous flies, but thorough investigationsof these species are more than likely to greatly increase theirstanding as disease carriers.The eggs are deposited in masses of ,as many as 300 and a singletiy may possibly deposit three batches. They hatch in from 10 to ~4hours after deposition.The larvre of C. erythrocephala may be distinguished from the housefly larvre by having usually nine but sometimes up to twelve lobes in theanterior (thoracic) spiracles; an anterior scabrous swollen ring on eachof the first eight segments of the abdomen, and a ventral groove oneach segment beneath; the sJ:igmal field concave, surrounded by threepair of tubercles above, and two large and one small pair below; thestigmal plates about once and a fourth their diameter apart, each withthree straight slits, directed principally toward the opposite p1ate; andalso, by having an anal pair of tubercles. The larval characters areillustrated by Hewitt and also by Banks.The larval period requires seven and a half to eight days at !'l3° C.(73.5° F.) and the pupal period fourteen days, according to Hewitt.Bishopp and Laake found the larvre to attain full growth in three to fourdays and the time from deposition of eggs to emergence of adults was 15to ~o days.THE SHEEP MAGGOTS On GREEN BOTTLE FLIESThe European sheep maggot fly, Lucilia s~ricata Meigen, is primarilyan outdoor fly but occasionally is found indoors, especially in farm andcountry houses. It is more brilliant than the Calliphoras, being of aburnished gold with a shining, bluish-green color. (.