Plant Diseases and bisects. 



103 



whose labors and discoveries resulted in the several feasible 

 and satisfactory methods of coping with the insect. 



" Introduction of parasites and predaceous species. — The 

 success which has attended the introduction from Australia of 

 Vedalia cardinalis has been phenomenal."^ Indeed, few who 

 have not kept in knowledge of the reports and the actual 

 condition of things can appreciate the remarkable character 

 of the results, not only because of the brief period required 

 therefor, but because of the thoroughness of the work of the 

 little ladybird and the moral and financial benefit to orange 

 growers which have followed in its wake. 



"The striking success of the experiment has served to fix at- 

 tention, not only of entomologists, but of fruit growers and 

 farmers, to this mode of dealing with injurious insects, and 

 there is no question but that the cases in which the experiment 

 may be more or less successfully repeated are numerous. Let 

 us hope, therefore, that the moral effect will be as great as its 

 practical effect in opening up means and wa3^s in the future, 

 as it should serve to remove the disposition to deride any ex- 

 penditure having such results for its object. Many fears 

 have been expressed lest after sweeping off the icerya the 

 vedalia, being so far as we now know confined to that species 

 for food, should perish and that the icerya, preserved in some 

 restricted places undiscovered by its enemy, would again 

 multiply and become destructive. I firmly believe what I 

 wrote in my last annual report as United States Entomolo- 

 gist, viz : 



" 'We may hardly hope, however, that the last chapter in 

 the story is written. On the contrary, it is more than probable, 

 and in fact we strongly anticipate that the icerya will parti- 

 ally recuperate ; that the vedalia will, after its first victorious 

 spread, gradually decrease for lack of food, and that the rem- 

 nants of the fluted scale will in the interim multiply and 

 spread again. This contest between the plant-feeder and its 

 deadliest enemy will go on with alternate fluctuations in the 

 supremacy of either, varying from 3^ear to year according to 

 localit}' or conditions ; but there is no reason to doubt that 

 the vedalia will continue substantially victorious, and that the 

 power for serious harm, such as the icerya has done in the 

 past, has been forever destroyed. We have learned, also, 



(*) See Annals Hort. 1889, 62. 



