4 Introductory. 



the majority of cases the insects may be found in every month of 

 the year. 



It is during the rainy seasons, or rather immediately after that 

 period, that we are able to take our Coccid enemies at a disad- 

 vantage. Their numbers have been reduced by a fungoid disease 

 to which they are specially subject at this season, and the survivors 

 are probably weakened from the same cause. It is now that 

 remedial measures can be best undertaken and insecticides will 

 have the best effect. An account of the most approved methods 

 of treatment will be found in an appendix devoted to the subject. 



Another fact that cannot fail to attract the attention of a 

 student of the Coccidai is the wide distribution of many of the 

 species. This is especially the case with those affecting fruit trees 

 Looking through our Ceylon list, we find individual species that 

 occur in all quarters of the globe. Mytilaspis citricola, for instance, 

 will be found wherever plants of the orange and citron family are 

 cultivated, while Diaspis amygdali attacks fruit trees of several 

 kinds in such widely separate countries as America, South Africa, 

 Ceylon, Japan, and Australia. The reason of this wide distribution 

 is not difficult to understand when we remember the ease with 

 which living Coccids may be transported with fruit and growing 

 plants. Year by year the commoner species of Scale Insects are 

 becoming more cosmopolitan. 



Every tree, shrub, or plant, would soon be completely overrun 

 with ' Scale-bugs,' and other insect pests, if it were not for the good 

 services of numerous natural enemies, which may be primarily 

 divided into the two classes of vegetable and animal. Under the 

 first class will fall the mould-like fungus that attacks and destroys 

 many Scale Insects during the wet season. In the second class 

 are the many insects that prey upon Coccid^e and their allies. The 

 predatory insects, again, belong to two distinct categories, external 

 feeders and internal feeders. 



The ' Lady-bird ' beetles are the principal agents among the 

 external feeders. Many species of these useful little insects live 

 entirely upon Scale-bugs, devouring them with avidity and some- 

 times entirely freeing a tree of these pests. The process may often 

 be observed where a colony of bugs has overrun some tree trunk. 

 Many of the individuals are seen to be mere empty shells, each 

 with a jagged hole in the back. Further on, one of the little 

 beetles, or its elongated alligator-shaped grub, may perhaps be 

 seen at work, greedily tearing open and devouring its defenceless 



