100 EVENINGS AT THE MICEOSCOPE. 



CHAPTER IX. 



INSECTS : THEIR MOUTHS. 



The parts of tlie mouth in different insects afford an 

 almost endless store of delightful observations ; and the 

 more as, with all their variety, they are found to be in 

 every case composed of the same essential elements. 

 You would not think so, indeed ; you would naturally 

 suppose — looking at the biting jaws of a Beetle, the 

 piercing proboscis of a Bug, the long elegantly-coiled 

 sucker of a Butterfly, the licking tongue of a Bee, the 

 cutting lancets of a Horse-fly, and the stinging tube of 

 a Gnat — that each of these organs was composed on a 

 plan of its own, and that no common structure could 

 exist in instruments so diverse. But it is so, as we 

 shall see. 



We may consider tlie various oro-ans of the mouth 

 as most harmoniously and perfectly developed in the 

 active carnivorous Beetles, the Carahidce, or ground- 

 beetles, for instance. Let us examine the head of 

 this black Scarites, from the garden ; and first from 

 above. 



In front of the polished head-shield, and jointed to it 

 by a broad transverse straight edge, is a four-sided 

 piece, forming an oblong square, nearly twice as broad 

 as long, a little convex, and marked with six little p'ts 



