Termites or "white ants," another misnomer, since they are not true ants, are also well-known ravagers whose deeds of destruction assume a serious aspect, especially in the tropics. "Humboldt," according to Shimer, "informs us that in all equinoctial America, where the white ants abound, it is infinitely rare to find papers or books that go back fifty or sixty years." Their destruction to timber has been the cause of serious accidents, at one time so weakening the supports of a dwelling that a whole dinner party was precipitated from the third floor to the basement. These pests belong to the order Isoptera. The American species is known as Termes flavipes, and several well-authenticated cases of their having done serious injury to books and bindings in this country are recorded. As the chief sustenance of these insects seems to be dead wood, it may be that the increased use of wood in paper will make modern books, which bookworms are said to scorn, more tempting than ever to them.
By opening quickly some old book which has lain long unused, one may see tiny pale creatures with knowing black eyes scurrying across the pages. These insects are known as "book lice," or by the Germans as "Staublaus" (dust louse). Entomologists have given them the high-sounding name Atropos divinatoria. They belong to the family Psocidæ, of the order Corrodentia. Some writers, beginning with William Derham, in 1701, are of the opinion that this delicate little creature makes a noise like unto that of the coleopterous insect called "death-watch." These little fellows are said to have stout jaws with which they do damage to books, dried plants, etc., "nibbling away the leaves and covers of the former."
Of all the insects that injure books perhaps the best known are the cockroaches, scientifically called Blattidæ, of which there are five species whose bookish habits are unquestioned. Many instances of serious damage done by them to the bindings of books are on record, the most important, perhaps, being that of the Natural History Museum Reports, at Albany, where Mr. J. A. Lintner found a hundred volumes or more so badly damaged by roaches that they could not be moved without coming to pieces. The United States Senate Reports, bound in cloth and leather, some fresh and new, have been badly damaged at Washington, in the efforts of these pests to get at the paste with which the covers were fastened to the volumes. The species known to commit these depredations are the "Croton bug" (Blatta germanica), smaller than the others, but considered by some writers as the worst pests of the family; a little larger species, called Periplaneta orientalis; and a large species, known as Periplaneta americana, or Kakerlac. Against two other species, Blatta australasiæ and Blatta gigantea, there is not so much evidence.
Among the moths, or millers, order Lepidoptera, are found several species which injure books, the best known being the Aglossa pinguinalis, commonly called "grease moth." The larva of this species is at first a pale, flesh-colored grub, but as it matures it becomes quite black. It injures bindings by constructing long "silken tubes," in which it remains until full fed. Sometimes they spin a web between the volumes, "gnawing small portions of the paper with which to form their cocoons." This species belongs to the family Pyralididæ. Of the family Œcophoridæ two species are known to injure books: Acompsia pseudospretella, and an undetermined species of Depressaria. Under the name Œcophora, William Blades describes the ravages of the former on two leaves of a "Caxton," and accompanies his remarks with a photographic illustration of the damaged leaves, from which it is at once seen how irregular is the gnawing of this species. The newspaper account of the finding of bookworms in the Lenox Library not long ago classed the larvæ found with this species.
The largest number of book-destroying insects are found among the beetles, of the order Coleoptera. To this group belong the "book borers." The species thus far considered have been more or less dilettantes in literature. The beetles, however, seem possessed with a true spirit of investigation, and when they undertake a piece of work in a serious fashion they go to the bottom of it, sticking close to the line laid down. This characteristic distinguishes these insects from all others, and makes it comparatively easy to determine when they have been at work in a worm-eaten volume. No less than sixteen different species of this order have been either detected in this work, or such strong circumstantial evidence has been found against them, that there is little doubt as to their guilt. Some insects seem to destroy books for the sheer want of something better to do; some do so in seeking the paste and sizing used in and about the books; others because the leather bindings are desirable material in which to undergo 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: Dermestidæ, Scolytidæ, and Ptinidæ. The Dermestidæ 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 bindings is Anthrenus varius, which 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 Dermestes 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 Anobium paniceum. Dermestes lardarius and Attagenus pellio are others of this family mentioned in the same category.
The family Ptinidæ includes two groups, Anobium and Ptinus, the first being generally known as the "death-watch," from the peculiar 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 Anobium paniceum. It is a cosmopolitan 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 trimmings, 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 Florence. The larvæ are about three to four millimetres in length, of a dirty-white color, head tinged with brown, and black mouth parts, with the abdomen strongly curved. The adult is a small, cylindrical, brown beetle from two to three millimetres in length, with head bent down and wing covers marked with fine punctate striæ.
Professor Poey made extensive observations of an insect in Cuba which had destroyed about four thousand volumes. He called it Anobium bibliothecarum, and Schwartz thinks the injury reported by Herminier from Guadeloupe should be attributed to the same species. Anobium striatum and pertinax have long been known to injure books by their "gnawing and burrowing," not only in and through the bindings, but also entirely through the volumes. Nicobium hirtum, a native of southern Europe, where its larvæ have been found doing like injury, is only locally abundant, and for this reason has never been considered a serious library pest. Schwartz says, "In one way or another the insect has found its way to North America, but has always been regarded as a great rarity with us."
The Ptinus group embraces Ptinus fur, Ptinus mollis, Ptinus brunneus, and Ptilinus pectinicornis, called by Leunis "Bücherbohrer." According to Butler, a peculiarity of this genius—that of dissimilarity of shape between the sexes—is well illustrated by the P. fur, the male being almost cylindrical, the female inflated or rounded at the sides; so much variation that they might be taken for two different insects. Ptinus brunneus, although similar to P. fur, is distinguished from it by being wholly of a light-brown color and destitute of whitish bands on the wing covers. Some writers speak of this species as the "book beetle," while Sitodrepa is spoken of as the "spice beetle." Dr. Henry Shimer makes the following statement regarding their method of boring: "They usually operate in leather-bound or half-bound volumes by boring galleries along in the leather.... They usually bore along quite under the surface of the leather, cutting it almost through; occasionally a small round hole penetrates through the leather to the outer surface."
One of the most famous cases on record of insects boring through books is that reported by M. Peignot, in which he states that twenty-seven folio volumes were pierced through in so straight a line that a cord might be passed through them and all the volumes raised by means of it. Different writers give the credit of this feat to different members of this group, so that the most that can be said is that it was the work of some member of the Ptinidæ.