EXPERIMENT STATION. 25 



DEPARTMENT OF BACTERIOLOGY. 



During the time covered by this report, the work of this 

 department has embraced the continued study of the biology 

 of ensilage, the life history and treatment of fungous diseases 

 of fruit trees and the potato, the study of the apple fruit in re- 

 lation to its structure and development, and the problems of a 

 biological nature concerned in its storaofe. 



The following is a preliminary report of the last-mentioned 

 subject: 



Storage of Apples. 



The term "fruit" has two significations. From a botanical 

 standpoint the fruit is the structure containing the seed, which 

 develops from the pistil or pistils of the flower. In common par- 

 lance, afruit is such a structure of a pulpy or juicy nature, which 

 is desirable for human food, either for the nutriment which it 

 contains, or for its palate-pleasing properties, or both. What- 

 ever may have been the original character of the apple, it has, 

 by long cultivation, been greatly improved until it is today one 

 of the most desirable fruits, and hence is of great commercial 

 importance. 



In the apple flower, the part which is to become the apple 

 lies beneath the petals and other conspicuous parts, forming 

 their support. After pollination it begins to grow in size, and 

 continues to do so throuo^hout the summer and earlv fall. The 

 growth takes place chiefly in the tissues which lie outside of the 

 seed vessels proper and form the edible pulp, while the seeds 

 develop in the central part, called the core. The whole is cov- 

 ered and protected by a thin but tough skin, which is rendered 

 w^aterproof by a coating of wax. Before maturity the apple 

 is hard and unpalatable, but as it ripens changes take place in 

 it with the result that it becomes softened or mellow, and an 

 agreeable taste and flavor are developed. The agreeable taste 

 of the apple depends largely upon the mixture of acid and sugar, 

 or sweet and sour, which it contains, each variety presenting its 

 own peculiar proportions. The flavor or aroma probably de- 

 pends upon small quantities or compounds of an ethereal nature 



