Household Pests and Their Treatment. 89 



Ordinarily these insects are not common enough to re 

 quire treatment. A little insect powder dusted about tables 

 and among papers may be sufficient. Wall papers, as far as 

 my observations extend, are damaged in the regions about picture 

 rails and window frames, the insects coming out from behind them 

 at night to feed. Blowing insect powder into the crevices behind 

 the frames is thus calculated to reach and destroy the silver 

 fish in their lurking places. Glue moistened with water and 

 dusted with arsenic will doubtless destroy many of them. A 

 similar bait of starch paste and arsenic is sometimes used about 

 shelves by librarians, but as already stated my own experience 

 with starch baits indicates that they are valueless for some of 

 the silver fish of our dwellings. 



FIG. 14. Under side of tip of abdomen of silver fish showing, A, B. C, 

 the pairs of imperfect limbs and, D, E, P, three terminal, jointed 

 appendages. Original. 



These insects measure nearly a half inch in length and 

 as the name implies are silvery white, the peculiar gloss being 

 due to microscopic overlapping scales with which the body- is 

 covered. There are no wings at any stage of their existence, 

 hence there are none of those abrupt changes known as meta- 

 morphoses, so highly characteristic of most insects. A pair of 

 slender feelers (antennae) arises from the head, while at the 

 hind end of the body are attached three similar slender stylets 



