320 OUR HOUSEHOLD INSECTS 



admire the excellent contrivance of Nature in placing 

 in Animals such a fire, as is continually nourished and 

 supply'd by the materials convey'd into the stomach, 

 and fomented by the bellows of the lungs; and in so 

 contriving the most admirable fabrick of Animals as 

 to make the very spending and wasting of that fire to 

 be instrumental to the procuring and collecting more 

 materials to augment and cherish itself, which indeed 

 seems to be the principal end of all the contrivances 

 observable in bruit Animals." The nervous system is of 

 the usual type, consisting of a pair of ganglia above the 

 gullet, in the head, and a chain of eleven pairs down 

 the body, beneath the digestive apparatus. The little 

 creature breathes by means of tracheae, like other in- 

 sects, and some of these may be seen through the skin 

 during life, or immediately after death, especially those 

 running down the legs. 



Lepisma saccliarina is essentially a vegetable feeder, 

 and the substance most in accord with its taste is 

 apparently starch. This preference makes it sometimes 

 a by no means insignificant foe ; for starchy substances 

 are so largely used in connection with books and papers, 

 that Lepisma may do serious damage in libraries and 

 museums if not carefully guarded against. Several 

 instances of this are on record, and doubtless many 

 more might be collected if the foe were more generally 

 known and more easily detected in the act of maraud- 

 ing; but as it is a lover of darkness and concealment, 

 and easily takes alarm, rapidly slipping away in a weird 

 ghost-like manner when interrupted, it is frequently 

 difficult to obtain anything more than circumstantial 

 evidence of its depredations. In 1879 Professor West- 

 wood exhibited to the Naturalists' Association a print, 

 the plain border of which had been eaten in holes by 



