In _Mallophora_ and _Promachus_, the venation is as represented in Fig. 129, where, as will be seen, the second vein (Fig. 129, _b_) forks, while in the genus Asilus (Fig. 130) the third vein is forked, though in all three genera the third joint of the antennæ (Fig. 128) ends in a prolonged bristle. One of the most common of these pests, which I am informed by Dr. Hagen, is _Mallophora orcina_, Wied, (Fig. 126) is one inch long, and expands one and three-fourths inches (Fig. 127). The head (Fig. 128) is broad, the eyes black and prominent, the antennæ three-jointed, the last joint terminating in a bristle, while the beak is very large, strong, and like the eyes and antennæ, coal black. This is mostly concealed by the light yellow hairs, which are crowded thick about the mouth and between the eyes. [Illustration: Fig. 129,] The thorax is prominent and thickly set with light yellow hairs. The abdomen is narrow, tapering, and covered with yellow hairs except the tip, which is black. Beneath, the insect is clear black, though there are scattering hairs of a grayish yellow color on the black legs. The pulvilli, or feet pads (Fig. 131, _b_) are two in number, bright yellow in color, surmounted by strong black claws (Fig. 131, _a_), while below and between is the sharp spine (Fig, 131, _c_), technically known as the empodium. I cannot give the distinctions which mark the sexes, nor can I throw any light upon the larval condition of the insect. The habits of the flies are interesting, if not to our liking. Their flight is like the wind, and perched near the hive, they rush upon the unwary bee returning to the hive with its full load of nectar, and grasping it with their hard strong legs, they bear it to some perch near by, when they pierce the crust, suck out the juices, and drop the carcass, and are then ready to repeat the operation. A hole in the bee shows the cause of its sudden taking off. The eviscerated bee is not always killed at once by this rude onslaught, but often can crawl some distance away from where it falls, before it expires. Another insect nearly as common is the _Mallophora bomboides_, Wied. This fly might be called a larger edition of the one just described, as in form, habits and appearance, it closely resembles the other. It belongs to the same genus, possessing all the generic characters already pointed out. It is very difficult to capture them, as they are so quick and active. [Illustration: Fig. 130.]