2 



On account of its always shunning the hght and its abihty to run 

 very rapidly to places of concealment, it is not often seen and is most 

 difficult to capture, and being clothed with smooth, glistening scales, 

 it will slip from between the fingers and is almost impossible to secure 

 without crushing or damaging. It is one of the most serious pests 

 in libraries, particularly to the binding of books, and will frequently 

 eat off the gold lettering to get at the paste beneath, or, as reported 

 by Mr. P. R. Uhler, of Baltimore, often gnaws off white slips glued 

 on the backs of books. Heavily glazed paper seems very attractive 



to this insect, and it 

 has frequently hap- 

 pened that the labels 

 in museum collections 

 have been disfigured 

 or destroyed by it, the 

 glazed surface having 

 been entirely eaten 

 off. In some cases 

 books printed on hea- 

 vily sized paper will 

 have the surface of 

 the leaves a good deal 

 scraped, leaving only 

 the portions covered 

 by the ink. It will 

 also eat any starched 

 clothing, linen, orcur- 

 tains, and has been 

 known to do ver}^ se- 

 rious damage to silks 

 which had probably 

 been stiffened with 

 sizing. Its damage in 

 houses, in addition to 

 its injury to books, 

 consists in causing the wall paper to scale off by its feeding on the 

 starch paste. It occasionally gets into vegetable drugs or similar 

 material left undisturbed for long periods. It is reported also to eat 

 occasionally into carpets and plush-covered furniture, but this is 

 open to question. 



The silver fish belongs to the lowest order of insects — the Thysa- 

 nura — is wingless, and of very simple structure. It is a worm-like 

 insect about one-third of an inch in length, tapering from near the 

 head to the extremity of the body. The head carries two prominent 

 antenna?, and at the tip of the body are three long, bristle-shaped 



Fig. 2.— iepi'sma domrstica: adult female— enlarged (original). 



