bb. Male with blackish abdomen, middle tibia with a tubercle beyond the middle. The larva with spiniferous appendages of which the dorsal and ventral series are short, the lateral series long and feathered ([fig. 101]) F. scalaris
aa. Apical cell (R) of the wing more or less narrowed in the margin; i. e., the bounding veins more or less converging ([fig. 108]).
b. The mouth-parts produced and pointed, fitted for piercing.
c. Palpi much shorter than the proboscis; a brownish gray fly, its thorax with three rather broad whitish stripes; on each border of the middle stripe and on the mesal borders of the lateral stripes is a blackish brown line. Abdomen yellowish brown; on the second, third and fourth segments are three brown spots which may be faint or even absent. The larvæ live in dung. The stable-fly ([fig. 110]) Stomoxys calcitrans
cc. Palpi nearly as long as the proboscis. Smaller species than the house-fly. The horn-fly ([fig. 167]) Hæmatobia irritans
bb. Mouth-parts blunt, fitted for lapping.
c. Thorax, particularly on the sides and near the base of the wings with soft golden yellow hairs among the bristles. This fly is often found in the house in very early spring or even in the winter. The cluster-fly, Pollenia rudis
cc. Thorax without golden yellow hairs among the bristles.
d. The last segment of the vein M with an abrupt angle. ([fig. 108]). The larvæ live in manure, etc. House-fly, Musca domestica
dd. The last segment of vein M with a broad, gentle curve ([fig. 102]).