1.  The “Anobium.”  Of this beetle there are varieties, viz.:  “A. pertinax,” “A. eruditus,” and “A. paniceum.”  In the larval state they are grubs, just like those found, in nuts; in this stage they are too much alike to be distinguished from one another.  They feed on old dry wood, and often infest bookcases and shelves.  They eat the wooden boards of old books, and so pass into the paper where they make long holes quite round, except when they work in a slanting direction, when the holes appear to be oblong.  They will thus pierce through several volumes in succession, Peignot, the well-known bibliographer, having found 27 volumes so pierced in a straight line by one worm, a miracle of gluttony, the story of which, for myself, I receive “cum grano salis.”  After a certain time the larva changes into a pupa, and then emerges as a small brown beetle.

2.  “Oecophora.”—­This larva is similar in size to that of Anobium, but can be distinguished at once by having legs.  It is a caterpillar, with six legs upon its thorax and eight sucker-like protuberances on its body, like a silk-worm.  It changes into a chrysalis, and then assumes its perfect shape as a small brown moth.  The species that attacks books is the OEcophora pseudospretella.  It loves damp and warmth, and eats any fibrous material.  This caterpillar is quite unlike any garden species, and, excepting the legs, is very similar in appearance and size to the Anobium.  It is about half-inch long, with a horny head and strong jaws.  To printers’ ink or writing ink he appears to have no great dislike, though I imagine that the former often disagrees with his health, unless he is very robust, as in books where the print is pierced a majority of the worm-holes I have seen are too short in extent to have provided food enough for the development of the grub.  But, although the ink may be unwholesome, many grubs survive, and, eating day and night in silence and darkness, work out their destiny leaving, according to the strength of their constitutions, a longer or shorter tunnel in the volume.

In December, 1879, Mr. Birdsall, a well-known book-binder of Northampton, kindly sent me by post a fat little Worm, which had been found by one of his workmen in an old book while being bound.  He bore his journey extremely well, being very lively when turned out.  I placed him in a box in warmth and quiet, with some small fragments of paper from a Boethius, printed by Caxton, and a leaf of a seventeenth century book.  He ate a small piece of the leaf, but either from too much fresh air, from unaccustomed liberty, or from change of food, he gradually weakened, and died in about three weeks.  I was sorry to lose him, as I wished to verify his name in his perfect state.  Mr. Waterhouse, of the Entomological department of the British Museum, very kindly examined him before death, and was of opinion he was OEcophora pseudospretella.