The following account[4] is just as applicable to-day as when written many years ago.
[4] Howard, L. 0., in Bulletin 4, new series, Division of Entomology, United States Department of Agriculture, pp. 58-59. 1896.
The adult insect is a small, broad-oval beetle, about three-sixteenths of an inch long, black in color, but is covered with exceedingly minute scales, which give it a marbled black-and-white appearance. It also has a red stripe down the middle of the back, widening into projections at three intervals. When disturbed it "plays 'possum," folding up its legs and antennæ and feigning death As a general thing the beetles begin to appear in the fall, and continue to issue, in heated houses, throughout the winter and following spring. Soon after issuing they pair, and the females lay their eggs in convenient spots. The eggs hatch, under favorable conditions, in a few days, and the larvæ, with plenty of food, develop quite rapidly. Their development is retarded by cold weather or lack of food, and they remain alive in the larval state, in such conditions and particularly in a dry atmosphere, for an almost indefinite period molting frequently and feeding upon their cast skins. Under normal conditions, however the skin is cast about six times, and there are, probably, in the North, not more than two annual generations. When the larva reaches full growth the yellowish pupa is formed within the last larval skin. Eventually this skin splits down the back and reveals the pupa, from which the beetle emerges later. The beetles are day fliers, and when not engaged in egg laying are attracted to the light. They fly to the windows, and may often be found upon the sills or panes. Where they can fly out through an open window they do so, and are strongly attracted to the flowers of certain plants, particularly the family Scrophulariaceæ but also to certain Composite, such as milfoil (Achillea millefolium). The flowers of Spiræa are also strongly attractive to the beetles. It is probable, however, that this migration from the house takes place, under ordinary circumstances after the eggs have been laid.
Fig. 3.—Feathers damaged by fabric pests. Injury has been done here by clothes moths and carpet beetles. They reduce feathers to a mat-like mass.
In Europe the insect is not especially noted as a household pest, probably owing to the fact that carpets are seldom tacked down. In fact, the writer believes that only where carpets are extensively used in this way are the conditions favorable for the great increase of this insect. Carpets once tacked down are seldom taken up for a year, and in the meantime the insect develops uninterruptedly. With the more general use of polished floors, and rugs which are often taken up and beaten, there is little doubt that the "buffalo bug" will eventually cease to be a household insect of importance. The insect is known in Europe as infesting museums, but has not acquired this habit to any great extent in this country. It is known to have this habit in Cambridge, Mass., and Detroit, Mich., as well as in San Francisco, Calif., but not in other localities. In each of these three cases it was imported from Europe in insect collections.
THE BLACK CARPET BEETLE.[5]
[5] Attagenus piceus Oliv.