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The Red Scale 



(Chrysomphalus aurantii) 



The Yellow Scale 



(Chrysomphalus aurantii var. citrinus) 



The Red Scale is in many respects a very different insect from 

 those we have already mentioned. The adult is about the diameter 

 of a pin head, nearly circular, and varies from gray to brick-red, 

 in color. The form on top rises gradually from the edge towards 

 the center, which is marked by a more or less distinctive pyramid 

 or nipple. It is well protected, with an armored shell above and 

 a tight film underneath making it very hard to kill by fumigation. 



The young are produced alive, not hatching from eggs, and at 

 all seasons of the year, though much more numerous in the warm 

 weather. 



Red Scale 'C. aurantii) (a) natural size of leaf; (b) female scale greatly 

 enlarged; (c) male scale greatly enlarged. 



In treating trees for its control, the best time is during the summer 

 or fall months when there is the largest proportion of young, but 

 good fumigation will bring results at any time, as there is never a 

 period when all the scale are resistant to the gas. However, this 

 is always a hard scale to eradicate entirely, and the best time for 

 fumigation is none too good, some practical men having stated the 

 Red Scale is as hard to kill as the Purple Scale. 



The Yellow Scale is so similar to the Red Scale that each is 

 often mistaken for the other, and the following are some of the 

 differences by which they may be distinguished. The Yellow Scale 

 is much more easily killed than the Red. It is a trifle broader, 



