Bitter Fit in Airples. 13 



I 



This series of experiments seems to point out that the first 



effect of the poison is to inhibit the action of the diastase, which 



it ultimately kills. The method adopted for the precipitation 



of the enzymes was essentially the same as was employed in the 



paperi on Enzymes and Latent Life of Seeds. 



The consideration into why, in some varieties, the disease is 



contracted earlier than others, and also why some varieties seem 



to be much more liable to bitter pit than others is probably 



connected with the time of opening of the stomata and lenticels, 



and also w^ith the characteristic textures of the different varieties 



of fruits. The sappy kinds seem to be more subject to the 



disease, though it has been observed to be present, more or less, 



in the majority of the Burnley trees, and as before stated, lead 



arsenate spraying appears to be particularly vigorous there. 



Following is a list of trees on which I found diseased specimens 



in February and March this year at Burnley Gardens : — 



Allington Pippin. Norfolk Bellfing. 



Anne Elisabeth. Occident. 



Bismarck. Ortley. 



Burwood. Prince Alfred. 



Cleopatra. Purity. 



Cooper's Market. Red Normanby. 



Dillington Beauty. Roundaway Magnum Bonum. 



Edgar's Red Streak. Royal Sovereign. 



Hockett's Sweet. St. Alban's Pippin. 



Jonathan. Stark. 



Julian. Sweet Lading. 



Laing's Best. Winter Colman. 



Lord Wolseley. Crab variety — 



Newtown Wonder. Fairy. 



Without exce^Dtion all the orchardists interviewed seemed 

 to consider Munro's favourite as an immune variety, and it 

 was not until the Horticultural Society's Show held last month 

 that I ever saw one of these apples affected in this way. Con- 

 sequently, though it cannot be considered as exempt, it appears 

 to be very resistant to bitter pit. The water containing the 

 dissolved poison can only enter a stoma or lenticel if the inter- 



2 Proc. Roy. Soc. London, ser. B., vol. Ixxxi., 1909, p. 420. 



