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Apple and Pear Sucker 



difference in the quality of the juices of the different varieties of the 

 apple trees — they seem to be the same, whether sweet or sour, and 

 they are not disliked by any batch of the larvae. 



No doubt there are different trees which are less heavily infected 

 than others, and there are some which are not infected at all. I doubt 

 whether the latter form the case of the immunity. The same variety 

 passes through all stages of infection — some with no larvae, while others 

 are heavily infected with them. It seems to be the case of the chance 

 distribution of the eggs of the apple sucker on different plants. 



I have noted down the results of my experiment with regard to 

 the immunity : 



Name of the variety 

 (1) Duchess favourite 



(2) Yellow in jesting 



(3) Warner's king 



(4) Stirling Castle 



(5) Early Julian 



(G) Worcester pearmain 



