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are known as "blister beetles" because they have a substance in their blood, called cantharidin, famous for its blistering properties and formerly much used in medicine. The female blister beetles of several species lay their eggs in the ground in regions frequented by grasshoppers, where the young on hatching can find the egg-pods of the latter. The little beetles (Fig. 12) hatch in a form quite different from that of their parents and are known as triungulins because of two spines beside the single claw on each of their feet, which gives the foot a three-clawed appearance. Though the young scapegrace of a beetle is a housebreaker and a thief, his story, like that of too many criminals, unfortunately, makes interesting reading,

Fig. 12. The first-stage larva, or “triungulin,” of the striped blister beetle (fig. 11 B). Enlarged 12 times.
(From Riley)

and the following account is taken, with a few omissions, from the history of Epicauta vittata as given by Dr. C. V. Riley:

From July till the middle of October the eggs are being laid in the ground in loose, irregular masses of about 130 on an average—the female excavating a hole for the purpose, and afterwards covering up the mass by scratching with her feet. She lays at several different intervals, producing in the aggregate probably from four to five hundred ova. She prefers for purposes of oviposition the very same warm sunny locations chosen by the locusts, and doubtless instinctively places ner eggs near those of these last, as I have on several occasions found them in close proximity. In the course of about 10 days—more or less according to the temperature of the ground—the first larva or triungulin hatches. These little triungulins (Fig. 12), at first feeble and perfectly white, soon assume their natural light-brown color and commence to move about. At night, or during cold or wet weather, all those of a batch huddle together with little motion, but when warmed by the sun they become very active, running with their long legs over the ground, and prying with their large heads and strong jaws into every crease and crevice in the soil, into which, in due time, they burrow