136 



THE MONTHLY BULLETIN. 



as large as those of the larvae of the green lacewing, as will be seen by 

 comparing the drawings of each. "When mature the larvae spin thick 

 white cocoons in which they pupate and from which they emerge 

 in several weefe as adulf insects. The cocoons are hidden in protected 

 places and are often found massed together in considerable numbers. 



This insect would be far more effective were it 

 not heavily preyed upon by an internal parasite 

 {Isodromus iceryce How.) which attacks the pupa) 

 in the cocoons. The writer has bred great numbers 

 of this parasite from the cocoons and has estimated 

 that only about ten per cent of the brown lace- 

 wings are able to escape the attacks of the parasite 

 and become mature. 



Baccha lemur O. S. 



A fly belonging to the family Syrphidce was 

 found feeding extensively upon the yerba santa 

 mealy bug. The adult flies are dark, one half inch 

 long with very slender bodies and a large black 

 spot near the middle of each wing. The larvae 

 evidently feed upon the egg masses or the adult 

 mealy bugs, which may or may not be enclosed 

 in the ovisac. This insect and the small dipterous 

 parasite, Leucopis hella, are evidently responsible 

 for holding the yerba santa mealy bug in check. 



ARTIFICIAL CONTROL. 



The cottony, waxy material secreted by the mealy 

 bugs renders them resistant to most of the methods 

 employed in the control of other scale insects. The 

 wax does not allow the ordinary sprays to penetrate 

 and in order to reach the body at all it is necessary 

 to employ an insecticide which will first dissolve 

 the wax. Oil emulsions usually do this. The cov- 



PiG. 53. Larva of eriug, also, scems to assist the mealy bugs in re- 



the brown lacewing, gigtiug fumigation, as it is ouc of the hardest pests 



Sj/mpherobius angus- . -, i ,-, ■ ^^ -, j^^ ^ i <• i • 



tus. Greatly enlarged. tO COUtrol by thlS method that WC haVC lOUnd 111 



(Author's illustration.) ^j^^ orchards. While, under some conditions, the 

 mealy bugs will succumb very readily to fumigation, under others it 

 is impossible to kill all without great injury to the tree. The splendid 

 success obtained in a few instances has often led to the belief that the 

 mealy bug could be easily and entirely exterminated by one or two 

 heavy fumigation doses, while poor results obtained under the most 

 favorable conditions have led others to believe that fumigation was 

 entirely futile in the subjugation of this pest. 



In a discussion of the control of the mealy bugs the writer Avishes to 

 take it up from two viewpoints : first, the general case of where the 

 mealy bugs are widely distributed in a district, and should be com- 

 mercially controlled as other scale insects; and second, from the view- 

 point of a small, isolated infestation, where the object would be to 

 entirely eliminate or eradicate, if possible, the infestation. 



