623 THE MICROSCOPE. 



distance, in comparison with its size. The body is 

 covered with numerous minute scales, mostly of a beau- 

 tiful silvery or pearly lustre, and curiously striated. 



Podura plumbea, Lead-colour Spring-tails, are generally 

 found in damp places, leaping about like fleas. They 



prefer a moist atmosphere, 

 some take to the surface 

 of the water in secluded 

 places ; their food seems 

 to be vegetable matter of 

 any kind in a stage of 



Fig. 286. Podura plunibea. (In the small decay; the little active 



circle the iusect appears life-size.) creatures are seen to leap 

 about if a stone in a damp situation in the garden is 

 turned up, or if a dark, damp corner of the cellar, about 

 the beer-barrel, is searched; or if we peep among the 

 roots of the ferns in the fern-case. Poduridae, varying in 

 form, colour, &c. are produced from eggs, undergo no 

 metamorphosis, are not parasitic, have from twelve to 

 sixteen simple eyes ; are furnished with strong mandibles, 

 and a broad, curious- looking snout, and a rather long 

 body, terminating in a bifid tail, which by alternately ex- 

 panding and contracting, enables them to leap great dis- 

 tances. The antennae are very long, and covered with 

 scales and fine hairs. To obtain the scales from the body 

 without damage which is certain to occur if the Podura 

 is touched by the fingers take a small test-tube and 

 quickly place it over the insect, when it instantly springs 

 up and clings to the side of the tube; insert a thin glass- 

 cover beneath, and close up the open end. One drop of 

 chloroform carefully administered instantly kills the in- 

 sect ; in a very short time this evaporates and leaves the 

 tube quite dry. By gently shaking the tube a number of 

 scales will drop off and adhere to the thin glass cover ; 

 remove this, and make it secure to the ordinary glass-slip. 



Mr. E. Eeck says, "that the best scales are obtained 

 from insects found in comparatively dry places." Mr. 

 S. J. Mclntire, in an interesting paper on the Podura, 1 

 confirms this statement, but believes that the " test-scale " 

 figured by Mr. Beck belongs to a distinct species. The 



(1) Science Gossip, March, 1867. 



