263 NEW YORK STATE MUSEUM 



or two, dying speedily after the fulfilment of the purpose of its 

 being. It takes no food, for in this stage it possesses no mouth or 

 digestive organs. 



A few species of the Coccidae are of service to us, such as the 

 Coccus cacti from which the valuable dye, cochineal, is obtained ; 

 the Carteria lacca which excretes the material known to us as shell- 

 lac ; from another species we have the commercial article known as 

 china wax ; and still another species occurring in Arabia produces 

 a solidified honey-dew called " manna," which " is thought by some 

 to have been the heaven-sent manna that nourished the Hebrews in 

 their wanderings." 



About 125 species of North American Coccidae have been 

 described, and others are being brought to notice each year, either 

 from having been previously overlooked, or recently introduced 

 from abroad. All of them are destructive in proportion to their 

 rapidity of multiplication and the greater or less economic import- 

 ance of the plants that they infest. 



