Beetles 271 



are slender white active grubs with a brown head and brownish patches 

 above and two small hooks at the end of the body. They feed on the meat 

 until full-grown, when they either burrow deeper into the meat or come out 

 and bore into the wooden receptacle holding it, and make a glistening paper- 

 like cocoon within which they pupate. 



The family Ptinidae is composed of small obscure brownish beetles that 

 would never attract our attention at all were it not for the injurious food- 

 habits of many of the species. The family includes a hundred and fifty 

 species, and among them a few notorious pests of rather unusual tastes. 

 As the Ptinids mostly live on dead and dry vegetable matter, it was not 

 improbable when I began a collecting expedition in a d ug-store that I should 

 find a number of specimens of this family. But to find a majority of the 

 canisters and jars containing vegetable 

 drugs in the condition of roots, stems, 

 leaves, etc., infested by beetles of this 

 family was unexpected. The most 

 abundant species on this collecting- 

 ground was Sitfodrepa panicea (Fig. 



3 7 3), which we may well call the "drug- 



, FIG. 373. The drug-store beetle, Re- 



store beetle. It was lound to be drepa panicea, larva pupa, and adults, 

 attacking blue-flag rhizome, comfrey- (After Howard and Marlatt; much 

 root, dogbane-root, ginger-rhizome, 



marshmallow-root, aniseed, aconite-tuber (deadly poison to us!), musk-root, 

 Indian-turnip rhizome, belladonna-root, witch-hazel leaves, powdered coffee- 

 seed, wormwood stems, flowers and leaves, thorn-apple leaves, cantharides 

 (dried bodies of blister-beetles), and thirty other different drugs! Larvae, 

 pupae, and adults were side by side in most of the canisters. Ptinus brun- 

 neus, a larger Ptinid, was in half a dozen jars, and the cigarette-beetle, 

 Lasiderma serricorne, suggestively named, though it feeds on tobacco in 

 almost any form, was living contentedly in a jar of powdered ergot. 



"Death-watch" is a name popularly applied to several species of Ptinids 

 because of their habit of rapping their heads so sharply against wood in 

 which they are burrowing as to make a regular tapping or ticking sound. 

 This name is claimed by species of Anobium, tiny, robust, hard-bodied, cin- 

 namon-colored beetles, ^ 3 T i ncn long, and also by Sitfodrepa panicea, our 

 drug-store beetle. Comstock records finding this species breeding in 

 large numbers in an old book, a copy of Dante's Divine Comedy, printed 

 in 1536. Librarians would call the beetle a "bookworm." 



Besides the small members of the family which feed on dried foods, 

 drugs, etc., there are a few larger species of very different habits, although 

 also destructive. The apple-twig borer, Amphicerus bicaudatus, % inch 

 long, dark chestnut-brown above and black beneath, is the best known of 



