MIGRATION, DISTRIBUTION, ACCLIMATISATION, ETC. 27 



trees in the open air any more than the " mealy bugs " 

 and numbers of other injurious Coccids from other 

 countries living under similar climatic conditions had 

 done. Coming, as the species does, from a subtropical 

 climate, I really do not think it would long survive out 

 of doors in our cold, damp climate. I was present also 

 at a meeting of the Entomological Society of London, 

 held March 2nd, when a discussion took place with 

 regard to the reported introduction of this pest, and 

 was glad to have my views supported by Mr. R. 

 McLachlan, F.R.S., and other Fellows of the Society 

 who were present. Furthermore I also received the 

 following communication from Dr. L. 0. Howard, the 

 entomologist of the United States Department of Agri- 

 culture, Washington, still further strengthening my 

 views with regard to the acclimatisation of the species 

 in this country : " I am glad you take the stand you do 

 about introduction into England. I honestly do not 

 think that the insect would thrive there out of doors, 

 although I may be mistaken. No doubt the insect could 

 reach you on California pears, and in my mind there 

 is no doubt as to the accuracy of the German statement 

 that it was found at Hamburg, but of course it takes an 

 expert to distinguish it from the closely related species 

 of Aspidiotus, and the ordinary observer is very apt to 

 mistake the small spots produced by the fungus, 

 Entomosporium maculatum, for this insect" (in lit., 

 March 14th, 1898). 



Superficially the San Jose scale insect differs but 

 very little from our indigenous Aspidiotus ostreaeformis, 

 but structurally they are very unlike. Photographic 

 illustrations of both these species are shown side by 

 side on Plate B, figs. 1 and 2 respectively. 



The danger to English horticulturists from the intro- 

 duction of injurious Coccids lies for the most part with 

 our cultivated fruits and flowers under glass, where, in 

 the absence of natural enemies, they thrive and multiply, 

 causing us annoyance, disappointment, and loss. 



It is highly improbable that the Coccids from warmer 



