264 COCCID^ — SHIELD-LICE. 



The Cocoidae, although they furnish an invaluable dye 

 and many articles of commerce, are among the most hurtful 

 of insects in gardens and hot-houses. In 1843, the orange- 

 trees of the Azores or Western Islands were nearly entirely 

 destroyed by the Coccus Hesperiduvi ; and in Fayal, an 

 island which had usually exported twelve thousand chests 

 of oranges annually, not one was exported.^ 



1 Baird's Cyclop, of Nat. Set. 



I 



