ANT COMMUNITIES 



The wings are thin aud transparent, with dark veins on 

 the anterior margin. 



The order Hemiptera is composed of beaked insects, 

 and the wings, where these organs are present, are of 

 the same texture throughout, and close, rooflike, over 

 the body. In several groups they are transparent, and 

 have many strong veins. In others they are tough and 

 opaque, and show many different colors. The head is 

 broad but usually short, without any neck, and has 

 the beak rising so far under the breast that it seems to be 

 attached thereto, and may be closely folded against it. 



The honey-dew which aphids yield, and which gives 

 the occasion for their peculiar connection with ants, is 

 obtained by the insertion of the beak into the tender 

 bark of the plant. The pumping apparatus is then set 

 in play and the sap withdrawn into the body of the in- 

 sect. It is a minute type of the mode of getting sugar- 

 water by "tapping" the trees in a sugar-maple camp in 

 Vermont or Ohio. The sap thus withdrawn probably 

 undergoes some slight chemical change within the in- 

 sect. It differs in taste from the sap of the plant, having 

 an acrid flavor, in some degree resembling the taste of 

 honey, thus justifying the ordinary phrase " honey-dew." 

 It does not, at least as far as the author's observations 

 have gone, proceed from the nectaries, or nectar tubes, 

 as has been commonly supposed, but is a fluid excrement. 

 This, however, differs from the ordinary excrement, which 

 is a whitish, semi-solid substance, voided in long cylin- 

 drical strings or minute whitish balls, which roll up like 

 quicksilver globules. 



The injury produced upon the plants by this tapping 

 results from this attempt of the insect to procure its 

 natural food. The numerous punctures made within 



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