Book-Lovers. 87 



by foot or hand to crush the life that dares obtrude its 

 uncleanly presence ,in her larder, but the cunning, swift- 

 footed Lepisma darts off, like a streak of light, to some 

 near-by crack or breach, where it manages to hide from 

 threatening danger. The bodies of these nimble, silent- 

 moving creatures being coated in a suit of shining mail, 

 which the arrangement of the scales so very much resembles, 

 they have a weird and ghostly look. This appearance, and 

 the swiftness of their movement, which the eye can hardly 

 trace, have led the vivid mind of man, in country town and 

 village, to dub them " silver witches." 



So fleet of foot are they, and so like a wave of blurred 

 light they cross the vision, that it is vain to try to figure 

 what they are in shape and look. In death they yield their 

 all of earth to prying science. Their body's form is narrow, 

 flattened; their legs in pairs of threes, each of six joints 

 consisting, the basal joints broad, flat, triangular, the tarsal 

 large, in number two, and armed at end with pair of claws 

 incurved. The three thoracic segments are very like in size, 

 and eight abdominals, of similar length and width. So weak 

 it seems the rather long abdomen is, that two pairs or six of 

 bristles, simple, unjointed, and freely movable, serve as 

 support, and also, as in other groups of insects, as organs 

 locomotive. 



The mode of antenna-insertion and the same prevails in 

 the entire family is much like that of the Myriopods, the 

 front of the head being flattened and concealing, as in the 

 Centipedes, the base of the antennae. Indeed, the head of 

 any of the Bristle-tails, as seen from above, bears a general 

 resemblance in some of its features to that of the Centipede 

 and its allies, and so, in a less degree, does the head of 

 the larvae of certain beetles and neuropters. The eyes are 

 compound, the individual facets constituting a sort of heap. 

 The mouth-parts are readily compared with those of the 

 larva of Perla, the rather large, stout mandibles being hid at 

 their tips by the upper lip, which moves freely up and down 



