PLANT-LICE, SCALE INSECTS, 

 TRUE BUGS, ETC. 



(Order Hemiptera.) 



This is another of the old and great orders of insects. It is. 

 one of the original Linnean orders and comprises those insects 

 known as the true bugs, true hce and scale insects. Nearly 20,00a 

 species have been described, but, as with the other big orders, 

 very many more yet remain to be studied, probably at least 

 three times as many as are now known. 



Although extremely variable in form and structure, all of the 

 Hemiptera have the mouth-parts formed for piercing and sucking 

 (not biting) and their metamorphoses are incomplete, the young 

 bug being active and formed much like the old one. In those 

 which have wings the wings are of two distinct types. In one 

 suborder the forewings are thickened at the base and the thinner 

 end parts lap over on the back. In the other type the forewings 

 are of about the same thickness throughout and are usually held 

 in repose sloping in a roof-shaped manner at the sides of the 

 body. 



The order as a whole is a most injurious one in its relations 

 with man. Although some of the true bugs prey upon injurious 

 insects the destruction of plants accomplished by others offsets 

 by far this benefit. In fact Sharp says: " if anything were to 

 exterminate the enemies of Hemiptera, we ourselves should 

 probably be starved in the course of a few months." 



The Hemiptera are divided into three suborders which we 

 shall consider separately. They are distinguished as follows: 



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