ENTOMOLOGY

COMMON FLIES AND HOW TO TELL THEM APART 139All the Sarcophagid or "flesh flies" can be readily separated from allthe other flies in the following table because their bodies are entirelygray. The head is rather a bright red, the top of the back has threeparallel dark stripes and the top of the abdomen has lighter reflectingareas, giving it somewhat 'of a checkered appearance.TABLE TO SEPARATE THE ADULT FLIESI. Grayish flies with from two to four longitudinal stripes more or lessindica ted on the thorax.1. Dark gray, medium sized fly; top of thorax with four parallel,black stripes; sides of abdomen with a large yellow area (variablein size and never definitely outlined); mouth-parts of 'the suctorialtype (see fig. lOa), never for biting; variable in size butMU.sCA DOME.JTICA "FIa. n.-Diagrammatic sketch of the house fly, MU8ca domeBtica.(Greene.)average about one-quarter inch in length. The common house fly(Frontispiece, figs. 11, Ua) also called typhoid fly.Musca domestica Linnaeus.~. Brownish-gray fly, slightly larger and broader than the house fly.Top of thorax with two long, parallel, black stripes and on eachside of these is a large black dot, below which is a black stripeabout half as long as the two long stripes. Abdomen with twoor three cone-sha:ped dark brown spots in the center and two 01'three round spots on each side (fig. 12c). Mouth-parts piercingor biting type (fig. lOb). Stable fly, also called biting house fly(fig. 46).Stomoxys calcitrans Linnaeus.3. Very dark gray fly, smaller and more slender than the house fly.Abdomen pointed and more conical in shape. Yellow spots on thesides definitely outlined' (fig. 12b). Mouth-parts are of the suctorialtype (fig. lOa). The small house fly (plate III, fig. 3).F awma camic'Ularis Linnaeus.4. Gray fly, a little larger than the house fly. (About the size ofStomoxys calcitram.) Top of thorax has two short, black