122 VIEWS OF THE MICROSCOPIC WORLD. 



found among saw-dust and damp wood. Its body and limbs arc cased in deli 

 cate scales, varying* from one-nine hundredth to one-one hundred and sixtieth 

 part of an inch in length ; and which are covered with lines diversified in ar 

 rangement as displayed in the above-named figure. Scales of very singular form 

 are found on the under side of the wing of a beautiful blue butterfly, called the 

 Lycoena Argus. In shape they resemble a battledore, with strings of beads run 

 ning lengthwise over the surface parallel to each other. The feathers upon the 

 wing of an insect are exceedingly numerous, for according to Leuwenhoeck each 

 wing of the moth of the silkworm contains more than two hundred thousand, 

 and the wing of this insect is small compared with that of many other moths ; 

 for one of the largest, the Atlas moth, the feathers of which are delineated in 

 figure 200, measures nearly a foot across the wings. In figure 201 is delineated 



Fig. 200. 



Fig. 201. 



several scales from the wing of the Death s-head moth, which receives its name 

 from bearing upon the surface of its thorax a large grey or yellowish spot, which 

 strongly resembles in form the front view of a human skull or Death s head. 

 On account of this peculiarity, and also from its great size, and the power it like 

 wise possesses of emitting a plaintive cry, this insect has been regarded with 

 superstitious awe. Reaumur relates, that appearing once in great numbers in 

 some districts of Bretagne, they were viewed with terror by the inhabitants, 

 as the sure precursor, and even the cause, of war and pestilence. In German 

 Poland it is termed the Wandering Death Bird ; and to the dreamy imaginations 

 of the superstitious, the head of a perfect skeleton is distinctly visible on the insect, 

 resting upon the limb bones crossed beneath ; while its cry is the moaning of a child 

 in pain and suffering. Its creation is regarded as the work of evil spirits, and the 

 reflections of those lurid flames amid which it arose, are discerned in the gleaming of 

 its glittering eyes. The rich hues of the scales of the Lepidoptera are supposed in 

 general to be due to the presence of coloring matter, but the more delicate tints 

 are regarded by Dr. Roget as an optical effect, produced by the fine lines upon 

 the surface of the scale ; a phenomenon identical with that observed in mother of 

 pearl, where the concentric flutings of the shell occasion the brilliant play ot 

 colors that adorn its surface. 



