98 



OUTLINES OF ENTOMOLOGY. 



small separate Order S IPHONAPTERA. They are bard, thick, 

 wingless creatures, having the body compressed at the sides and 

 sparsely hairy. In place of the usual compound eyes they have two 

 ocelli. The pointed head is armed with backward pointing teeth. The 

 legs are stout, with the thighs greatly thickened, giving them their 

 wonderful leaping power. The eggs are scattered about in untidy 

 human dwellings, dog kennels and the like, and the slender maggot- 

 like larvae feed in the dust and organic particles that accumulate in the 

 cracks of floors, under rugs and similar hiding places. When ready to 

 transform the larvae enclose themselves in silken cocoons. The human 

 flea is Pulex irritans, Linn., while P. canis, Dug., affects the dog and 

 cat. The tropical " jigger,' 7 "chigoe" or "-chique" ( Sarcopsylla pene- 

 trans} is the pest of hot, sandy regions, but must not be confounded 

 with a small tick a species of mite that occurs further north, and 

 also burrows into the skin and causes sores, and which is likewise often 

 called a "jigger." 



CHAPTER XXIV. 



Order V. HEMIPTERA.. 



[Fig. 40.] 



Harlequin Cabbage-bug (Murgantia histrionica, Hahn. after Riley. a, b, larva and 

 pupa (nymphse;; c, eggs natural size; d, e, same magnified; g, h, perfect bug. 



This Order derives its name from a compound Greek word signi- 

 fying half-wing, and refers to the half membranous, half-leathery (cori- 

 aceous) structure of the wings of many of the representatives. It con- 

 tains the only insects that may, with perfect accuracy, be called bugs. 

 The term "bug," so generally but incorrectly applied to many kinds of 

 insects, is supposed to have had its origin in the word "bug-bear," as 

 something frightful or dangerous, and it is most fitting that, correctly 

 used, it should refer to the division which includes such insects as the 

 bed-bug, louse and similar objects of dread and disgust. 



