290 ENTOMOLOGICAL SOCIETY 



Naples, and also throughout southern Spain, and, so far as the 

 foliage and twigs of the trees were concerned, a clean, bright, and 

 healthy appearance was uniformly noted, as though they had 

 never been subjected to any insect attacks whatever, and this not 

 withstanding the fact that many of the trees were seemingly 

 several hundred years old. In other words, there was no indica 

 tion of special damage by scale or other insects. This is certainly 

 in strong contrast to conditions noted by the writer in California, 

 where, under similar circumstances, the olive and citrus trees are 

 often infested and blackened by the presence of Lecanium olece 

 and other scale insects. The excellent condition of the olive and 

 citrus groves, particularly the former, of Europe is not due to any 

 special care given them. In fact, it is to be doubted if any of 

 them, in the regions visited, have ever been treated in a general 

 way for insect pests. Their freedom from scale is also not ex 

 plained by the absence of the insect itself, because the discovery 

 of rare examples here and there, and especially in old gardens, 

 was sufficient to prove its occurrence, if the fact were not other 

 wise well known. What has been said of the olive applies with 

 equal force to the citrus fruits, and, in a general way, to other 

 fruit and forest trees. 



For most of Europe the conviction is forced upon one that 

 climate has more to do with this immunity from insect enemies 

 than any other agency. The cooler and shorter summers of mid 

 dle Europe, comparable to our fall or early winter, almost, do 

 not foster the multiplication of insects as do our longer and very 

 hot summers. This can hardly apply with equal force to Spain, 

 at least to the olive and citrus districts. Here, however, it may 

 be inferred that the extreme dryness and heat of the summers 

 may have the effect of keeping scale insects in check, as do the 

 same influences in exceptional seasons in California. On this 

 side the Atlantic it may be that the greater moisture, in connec 

 tion with the long, hot summers in Florida, the West Indies, and 

 the coast region of California, is the predisposing cause which 

 leads to our serious affliction with scale insects. 



The writer is rather inclined to doubt, also, the belief, frequently 

 expressed, that parasitic and predaceous enemies are extraordi 

 narily important in Europe, at least so far as the enemies of fruit 

 trees and cultivated plants are concerned. That they are more 



