Fig. 



-The citrophilus mealybug : Immature stages of 

 the female. 



4 BULLETIN 1040, TJ. S. DEPAETME^iTT OF AGEICrLTUEE. 



HOST PLANTS. 



The citrophilus mealybug is of importance commercially prin- 

 cipally because of its infestation of citrus plants. The insect does 

 occur, however, on a large number of other plants, principally orna- 

 mentals, upward of 

 30 different species 

 being listed as hosts. 

 On the citrus fruits 

 it possibly shows its 

 most rapid develop- 

 ment on lemons, fol- 

 io wered b}' grape- 

 fruit, navel oranges, 

 and Valencia or- 

 anges, in the order 

 given. It has been 

 observed to develop 

 very rapidly on the 

 rhubarb, potato, 

 grevillea, walnut, grape, and on species of Coleus and Pittosporum. 



DESCRIPTION AND LIFE HISTORY. 



The synonymy of the citrophilus mealybug was first correctly de- 

 terminated by G. F, 

 Ferris in August of 

 1919.^ As stated, this 

 insect was first con- 

 fused with the com- 

 mon mealybug and 

 later, by Essig, with 

 Baker's mealybug. 

 Clausen, in Septem- 

 ber, 1915, noted cer- 

 tain differences in 

 him to describe it as 

 characters which led 

 a new species {P. cit- 

 rophilus) but Ferris 



found that the same ^^'^'- ^- — "^^^^ citrophilus mealybug : Mature stages of the 



female. 



insect had been de- 

 scribed by Mr. E. E, Green during May, 1915, as P. gahani from 

 specimens taken from Ribes sangioinea in London, England. Un- 



6 Ferris, G. F. Observations on sojie mealy-bugs (hemiptera; coccidae). 

 Jour. Econ. Ent., v. 12, no. 4, p. 292-293. 1919. 



In 



