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F. C. WILLCOCKS — A MEALY BUG 



The nodular white masses on the side o£ the twigs should be noted ; they are 

 formed by mealy bug colonies covering the sites of old leaf-scars. 



The insects produce a large amount of sticky " honey-dew," which falls 

 down on to the pavement below the trees, forming spots somewhat like rain- 

 drops. In paved streets one can readily detect an infested tree by the 

 numerous honey-dew spots thus produced. Dust collects to such a degree 

 over the site of the spots that the level of the pavement is perceptibly raised 

 thereby. The honey-dew appears to be secreted more abundantly during 

 the summer than at other periods of the year. Ants are very fond of this 

 secretion, and visit the insects to obtain it. 



Fig. 4. — Compound leaf of lebbek, showing colonies of the mealy bug on 

 the leaf-petioles and elsewhere. 



The males of D. perniciosus are by no means rare, but they do not appear 

 to be in any way proportionate to the females, which far outnumber them. 

 It is probable, therefore, that many of the females reproduce partheno- 

 genetically. 



The Appearance of the Infested Irees. 



In the case of a bad attack of this pest, the whole crown of a tree may be 

 killed in the course of a few months. The leaves turn brown, die and fall ; 

 finally the twigs and minor branches die back. Infested trees which have 



