ENTOMOLOGY

IS!!SANITARY ENTOMOLOGYbreed in the flesh causing external myiasis. This species attacks ulcersand sores of men and animals. Its most common attack on sheep andcalves is made on the soiled rumps of animals suffering from diarrhea.No doubt the flies also serve as distributors of the diarrhea.The larva has eight-lobed ant~rior spiracles. The same number oftubercles margin the stigmal plate behind as in Calliphora, but they aresmaller and sharper. The stigmal plates are about one-half theirdiameter apart, each with three straight slits, directed somewhat towardeach other, but also downward.Undoubtedly under battle front conditions this fly can be expectedto visit human wounds and breed in them even more readily than Calliphora.It has been shown by Cao to transmit anthrax with equalease. .Several other species of LucHia have like habits, and the larvre oftwo of these, L. caesar Linnaeus (not sericata Meigen), and L. sylva rumMeigen have been described and illustrated by Banks.The larvae of L. caesar measure 10 to 11 mm. in l~ngth and have notadequately been separated from Calliphora erythrocephala. The larvalperiod averages about fourteen days and the pupal stage about thesame. Bishopp and Laake state that in Texas, during warm weather,the larval period ranges from three to twelve days, the pupal stage fiveto sixteen days and the total developmental period eleven to twenty-fourdays. This ~y is illustrated in plate I, Fig. 2.OTHER SCREW WORMS AND DLOW FLIESThe question of myiasis, which covers screw worms and blow flies, is tobe considered in separate lectures (Chapters XII and XIII), but mentionmust be made of them at present because undoubtedly many infectiousdiseases are carried by these insects which attack alike live flesh throughwounds, and dead animals. I would hardly hesitate to claim thatprobably all such flies may carry anthrax at least, and probably do carryother diseases.Bishopp, Mitchell, and Parman (1917) describe quite fully the habitsof the common American screw worm, Chrysomya macellaria Linnaeus 4(plate I, fig. S, plate II) which breeds in both carcasses and flesh wounds(plate IV). They also treat the black blow fly Phm·mia regina Meigen(plate I, fig. 4), and other species. The large hairy blow fly, Cynomyiacadaverina, Robineau-Desvoidy, and the gray flesh flies Sarcophagate:cana Aldrich, S. tuberosa var. sarmcenioides Aldrich, S. sarraceniae• An appeal has been made to the International Commission on Zoological Nomenclatureto retain Chrysomya in the sense with macellaria as type.