than the elytra; the legs are long; the antennae are long, filiform, 
and inserted on the front of the head; and the elytra are usually 
very convex and shiny. The majority of our native species breed 
in old grass roots or in the bark of dead twigs of trees. Certain 
other species are destructive in warehouses and museums where 
they attack collections, to seasoned wood or logs left lying in the 
woods too long, to wood in old buildings, and to stored products. 
The white-marked spider beetle, Ptinus fur (Linnaeus), a cos- 
mopolitan species, is frequently found damaging dried vegetable 
and animal materials in warehouses and museums. Infestations 
also occur in pine and oak woodwork in these structures. 
The brown spider beetle, Ptinus clavipes Panzer, attacks pine 
boards in old buildings. 
FAMILY BRUCHIDAE 
SEED BEETLES 
Members of the family Bruchidae are distinguished by their 
compact and usually oval bodies, their small heads which are pro- 
longed into beaks, and their short wing covers which leave the tip 
of the abdomen exposed. The larvae are quite small and feed al- 
most entirely in the seeds of plants. 
Amblycerus robiniae (F.) is occasionally a pest in eastern 
United States. The female deposits her eggs on the pods of honey 
locust and the larvae feed on the seeds within the pod. Adults are 
reddish-brown and about 7 mm. long. The body is clothed with 
grayish-yellow hairs and there are five rows of black spots across 
the elytra. Gibbobruchus mimus (Say) breeds in the seeds of red- 
bud and Caryobruchus gleditsiae (L.), in palmetto. 
FAMILY CHRYSOMELIDAE 
LEAF BEETLES 
The leaf beetles comprise one of the larger families of Coleop- 
tera, with more than 1800 species occurring in the United States 
alone. The adults usually are medium-sized or small, short-bodied, 
and more or less oval. The legs are generally short; but in some 
species the femora of the hird pair are enlarged. There is great 
variation in coloring and markings, occasionally even within a 
species. In some species the entire body, elytra, and legs may have 
a bright metallic sheen. Some are hairless; others are pubescent 
or covered with scales or scale-like hairs. 
Leaf beetle larvae are usually soft-bodied and frequently have 
highly pigmented or well-chitinized sclerites on the integument. 
They vary greatly in shape, depending on their feeding habits. 
The head usually protrudes, except in the leaf miners, and is bent 
downward for feeding. The body varies greatly in shape from 
short and compact to depressed cuneiform, depending on whether 
the larva is free living or a leaf miner, casebearer, or root feeder. 
All members of the family feed on the foliage of plants as 
adults or larvae, or both. The adults are diurnal and are usually 
slow moving. Species that are exposed in the larval stage feed 
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