INJURIOUS TO THE LEBBEK TREES OF CAIRO. 



125 



branch (fig. 2). Aoain, the insects are very frequently found at the base 

 of the small shoots which sometimes grow out from the trunks of the trees. 



So far we have no details as to the time elapsing between the hatchincr of 

 the larva? and the formation of the ovisac and subsequent oviposition ; nor 

 as to the changes in the external appearance which takes place between. these 

 stages. The larvte are sparsely covered on the dorsal surface with a white 

 secretionarv substance, which becomes more marked in the later stages and 

 apparently corresponds to the segmentation of the bodv- 



Fig'. 3. — Growing- point of lebbek attacked Idj the mealy bug. 



When the globular ovisacs have developed, the insects impart a very 

 striking appearance to the twigs and branches they infest. The latter appear 

 to be covered with masses of pure white, somewhat felted, cotton-wool-like 

 material. So marked is this appearance that writers in the local papers 

 have been led to describe the attack of this pest as a kind of leprosy of the 

 trees. The photograph (fig. 5) of twigs taken from the ^' crown " of a badly 

 infested tree will explain this appearance better than a written description. 



