278 Bugs, Butterflies, and Beetles 



even shock the sensibilities of the most particular 

 persons. But the mention of an oyster-shell 

 bark-louse will sometimes cause a fruit grower and 

 farmer to use words outlawed in well-regulated 

 society. The reason of this is, because this scale 

 does great damage to the fruit trees. 



The scale (Fig. 259) is another undesirable 

 citizen which emigrated from Europe to the United 

 States. It does the most damage north of the 

 Mason and Dixon line, and is called the oyster 

 shell because the little thing, which is only one- 

 twelfth of an inch in length, is something the 

 color and very much the shape of a tiny oyster. 



You will sometimes find scale insects on a 

 potted plant in a conservatory, often on the maple 

 and fruit trees in your yard or orchard, and they 

 are plentiful in the green-houses of the florists, 

 where they may be seen plastered on the bark of 

 the orange and lemon trees. The scale is a sort of 

 bowl-shaped shell which fits over the insect and pro- 

 tects it from weather and bug-eating bugs. (Fig. 

 259 shows the under side of one of these scales.) 



Some of the scale insects are very useful. The 

 Lacca of India produces the stuff called lac, of 

 which sealing wax and varnishes are made. In Mai- 



