2+6 POPULAR SCIENCE MONTHLY. 



because the leather bindings are desirable material in which to un- 

 dergo transformation; and, again, others haunt book shelves and books 

 in search of prey in the form of living creatures. But among the 

 beetles are found tiny little grubs that seem to have a genuine intent 

 to destroy; that set out deliberately to wreak vengeance on man's 

 record of his thoughts, deeds, and discoveries, and, as if knowing the 

 means which man uses to destroy, have sought to imitate him in the 

 effects produced. As a result we find books filled with small, round, 

 shotlike holes strongly suggesting the results which might follow 

 from the use of the family Bible by the restless boy as a target for his 

 first shotgun. 



The book-destroying beetles are all grouped under three families : 

 DermestidoB, Scolytidce, and Ptinidce. The Dermestidce include the 

 " flower beetles " and the well-known " carpet bug." The species of 

 which there can be no doubt as to its disposition to pierce book bind- 

 ings is Anthrenus varius, w^hich Glover says " is a very pretty insect 

 when examined under a magnifying glass, being beautifully marbled 

 or variegated with black and gray." Another member of this family, 

 against which there is less evidence, is Dermesies chinensis, so named 

 by Dr. L'Herminier, of Guadeloupe, who reported a loss of nearly 

 four hundred volumes from its ravages. Erichson believes this to 

 have been the well-known Anohium paniceum. Dermestes lardarius 

 and Attagenus pellio are others of this family mentioned in the same 

 category. 



The family Ptinidce includes two gi'oups, Anohium and Ptinus, 

 the first being generally known as the " death-watch," from the pecul- 

 iar sound, like the tick of a watch, which is produced by striking 

 against a hard substance with their tiny jaws. Superstitious persons 

 have long considered this noise an omen of death, hence the name. 

 Instead of an ill omen, this noise proves itself to be a love-call between 

 the sexes, and may be imitated accurately enough to elicit a response. 

 One of the best known of these beetles is called Sitodrepa panicea, 

 generally known in Europe as Aiiohium paniceum. It is a cosmopoli- 

 tan feeder, having a reputation in several different fields of activity, 

 commercial and scientific as well as literary. To druggists it is known 

 as " the worm," and their stock of ginger, rhubarb, Cayenne pepper, 

 nux vomica, and belladonna root all appear to be equally to its liking, 

 tin foil being no formidable barrier to its persistent search. Leather 

 dealers have suffered from the destruction wrought by this little fellow 

 to such an extent that whole cases of boots and shoes, carriage trim- 

 mings, etc., have been ruined. To this species belongs the insect found 

 a few years ago at work in a volume of Dante's Divine Comedy, which 

 had been sent to Cornell University library from Elorence. The 

 larvae are about three to four millimetres in length, of a dirty-white 



