The primary purpose of the sting is to paralyze or kill their prey, although it becomes more important as a weapon of defense with insects which do not prey upon or parasitize other creatures. Although the solitary insects use their poison as a means of personal defense if attacked or imposed upon, the social insects such as ants, social wasps and hornets, honeybees, and others, rally to the defense of their nests and in mass attacks against an intruder may cause painful and sometimes serious injury. Although the small amount of poison introduced beneath the skin by the sting of one of these creatures usually causes only temporary discomfort, there are sometimes after effects which may be more intense and of longer duration with some persons than with others. In general, stinging insects may be considered more as a nuisance than a menace, although a person attacked by a large number, or subjected to their stings for some length of time, might receive serious and perhaps fatal injuries. Known deaths have been caused by the sting of imported fire ants in southeastern States. The species is believed to be spreading. Treatment by a physician may include the use of ACTH and calmitol. Although ants and velvet ants are commonly considered as wingless, they are, actually, winged. Male velvet ants have wings whereas the females are normally without wings. The females have a very effective sting, and if picked up or pinched they make every effort to use it, at the same time emitting a peculiar faint squeaking sound. True ants, of which there are hundreds of species, are social insects living in colonies containing the mother, or queen, which becomes wingless after fertilization; numerous workers, or non-fertile females; and young winged males and females. [Illustration: _Velvet ant_] _Control of ants_ Ants of various species are numerous on the desert, some of them becoming serious household pests, difficult to control. There are effective ant poisons on the market, but the surest method of control is to find the nest and destroy it. Ants that are household pests usually are either grease eaters or sweet eaters, and the proper poison for the specific type should be obtained in attempting to rid the house of these insects. _Wasps, hornets, yellowjackets, bees_ Wasps, hornets, yellowjackets, and bees of many species are common in the desert, some species being solitary in habit while others live in colonies or nests which they defend with great pugnacity. [Illustration: _Bumblebee_] Although humans have little to fear from these insects if they leave them strictly alone, some species select nest sites beneath overhanging eaves or in attics or lofts, thus becoming persistent pests. They are usually tolerated until one or more members of the family are stung.