76 EVENINGS AT THE MICROSCOPE. 



cliffs that border the sea- shore may often be found some 

 wingless but active Insects, which are endowed with the 

 power of leaping in great perfection. From their hinder 

 extremity being furnished with long projecting bristles, they 

 are sometimes called Bristle-tails, but naturalists desig- 

 nate the genus Machilis. If you can get one sufficiently 

 still to examine it, you will be delighted with the lustre of 

 its clothing, which appears dusted all over with a metallic 

 powder of rich colours, red, brown, orange and yellow, 

 foiled by dull lead-grey in places. 





BRISTLBXTAIL. 



(Slightly enlarged.) 



If you touch one of these nimble leapers, though ever so 

 lightly, you will see the result on your finger-ends ; for 

 they will be found covered with a thin stratum of the 

 finest dust, which displays the coloured metallic reflections 

 seen on the insect. By touching one with a plate of glass 

 instead of your finger, you will get the same dust to adhere 

 to this transparent medium, by applying which to the 

 microscope you may at once discern the marvellous nature 

 of the raiment with which the little creature is bedecked. 



The dust is now seen to be composed of myriads of thin 

 scales, mostly regular and symmetrical in their forms, 

 though varying exceedingly among themselves in this re- 

 spect. Some are heart-shaped, some shovel- shaped, some 

 round, oval, elliptical, half round, half elliptical, long and 



