A closely-allied and somewhat smaller species of _Anobium_ common in houses is of a more voracious character, not confining itself to dry wood, but eating bread, biscuits, rhubarb, ginger, and even cayenne pepper. This second kind, called _Anobium paniceum_, is the real “book-worm”; it gets into old libraries, and the grubs bore their cylindrical tunnels from cover to cover of the undisturbed volumes. In a public library twenty-seven folio volumes standing side by side were perforated in a straight line by one individual _Anobium_ grub or book-worm, and so regular was the tunnel thus eaten out that a string could be passed through the whole length of it, and the entire set of twenty-seven volumes lifted up at once by it. There are one or two other grubs which less commonly injure books, and pass as “book-worms.” But the most notable of the insect enemies of books and papers is a curious little wingless insect which never passes through a grub stage of existence, but hatches out in the complete form of his parents. He is about a third of an inch long, has the shape of an elongated kite, with a long tail and six legs, and is called by old writers “the silver-fish,” and by entomologists _Lepisma_ (Fig. 63). This little pest does not burrow, but nibbles, and has destroyed many a valuable old document and ancient book. Paste and sugar are a great attraction to him, and he will destroy a boxful of printed labels or a valuable manuscript, leaving only the ink-marked parts untouched, but ready to crumble.