44 The Microscope. 



drawing could convey an idea of their radiant bril- 

 liancy and lovely colour. 



These two last-mentioned objects are exceedingly 

 interesting when viewed by transmitted light ; small 

 fragments of them should be mounted for this pur- 

 pose. The shell of the brown beetle (fig. 2) appears 

 of a fine golden hue. The scales are of the same colour, 

 but appear as if sharply drawn in pen-and-ink lines ; 

 and in the vacant spaces the whole shell is covered with 

 a very curious system of lines, crossing each other in 

 the way called te cross-hatching " by engravers. This 

 same singular appearance occurs also in the shell of 

 the green weevil, and with many variations as to 

 arrangement and size, in all weevils which I have 

 happened to examine. It is particularly conspicuous 

 in the diamond beetle of Brazil, which is also one of 

 the weevils, and well known as a splendid microscopic 

 object when viewed by reflected light. 



The green weevil's shell shows still better than 

 that of the brown, as a transparent object. We see 

 the same golden ground, but the scales, instead of 

 being colourless, become a lovely red, tinged with 

 orange when over the wing-case, and with bluish 

 pink when they happen to show beyond the edge of 

 the fragment. 



The scales of fishes are interesting and pretty ob- 

 jects when viewed with the lower powers of the micro- 

 scope. Fig. 4 represents the scale of the perch. When 

 magnified four diameters we can easily make out the 

 graceful curving lines which cover it; these lines 

 appear as if continuous, and parallel to each other. 



