PART II —LIST OF THE INSECTS OF NEW JERSEY. 



Order THYSANURA. 



The order Thysanura contains the so-called Spring-tails and Bristle-tails : 

 minute wingless creatures with obscurely-developed mouth parts, no transfor- 

 mations, living usually in damp places in or among decaying or fermenting 

 vegetation or under bark. 



The latter type are called Spring-tails, because 

 they have the power of leaping by means of a 

 pair of anal appendages bent under the body, 

 and these are the minute creatures often seen 

 in potato or root-cellars when decay sets in, on 

 the surface of manure-beds early in spring, 

 where they cover the soil in untold numbers, 

 and hopping about on the surface of the water 

 when meadow or bog-land has been flooded by 

 a rain. On recently-flowed cranberry bogs acres 

 of water-surface may be seen covered by them 

 in late fall 



Fig. 8. 



Fig. 9. 



Fig. 7. 



Fig. 7. — Silver-fish, Lepsima sp ; very much enlarged. 



Fig. 8. — Podurid, commonly found on manure beds ; the 

 spring not visible because curved beneath the body ; much 

 enlarged. 



Fig. 0. — Podurid, spriDg extended to show the appearance 

 oi the entire insect in outline ; much enlarged. 



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