PHASES IN THE LIFE HISTORY OF NON-BITING FLIES 133 



Pl.vte I. — Screw worms and blow flies. Fig. 1 (iipf^er left). — The blue bottle fly, Cal' 

 liphora vomitoria. Fig. 2 (upper right). — The green bottle fly, Lucilia caesar. Fig. 

 3 (lower left). — The American screw worm, Chrysomi/a macellario. Fig. 4 (lower 

 right).— The black blow fly, Phormia regina. (Howard and Pierce, photos by 

 Dovener.) 



