70 ASSOCIATION" OF ECONOMIC ENTOMOLOGISTS. 



of getting a fair standard of comparison was a little more difficult ; 

 but by banding the unsprayed trees and catching two-thirds or over 

 of the first-brood worms it was thought that the few remaining 

 worms in excess of the number on a sprayed tree would be so evenly 

 scattered among the surrounding trees, especially where the unsprayed 

 trees were well distributed through the block, that they would fairly 

 represent the average distribution of the worms in the orchard. The 

 results in the second brood have in every case agreed so remarkably 

 with those in the first that there seems to be no question but that this 

 method was fairly accurate. 



All the tests have shown that the variation in the number of worms 

 attacking trees of equal size is very slight, as compared with the vari- 

 ation in the number of apples that they may bear; therefore the 

 method of comparing the actual number of wormy apples is much 

 more accurate than the method of comparing percentage of sound and 

 wormy fruit. 



In these tests none of the wormy apples from the first brood has 

 been found on the trees at picking time, and the percentage of those 

 of the second brood remaining has varied so greatly, under different 

 conditions and on different varieties, that results, based on percentage 

 of wormy fruit at picking time, appear to be of doubtful value at 

 best, and where they have included different varieties in the same 

 test, of no value at all. 



WHAT CONSTITUTES THOROUGH EARLY SPRAYING. 



If the first spray is applied for the purpose of placing poison in the 

 calyx cups — and all will agree to this. I think — then the test of the 

 efficiency of such a spray will be the amount of poison found in the 

 cup after it has closed. Now, paradoxical as it may sound, it is not 

 as easy to spray into an open calyx as it is into one that has nearly 

 closed. This will be made clear by referring to figure 4, subfigure 1, 

 where a cross section of an open cup is shown with- the pistil in th( 

 center and the circle of stamens forming a tight roof above, as seen at 

 la. A week or ten days later the calyx lobes have nearly closed above, 

 the opening being filled with the stamens and pistils, as seen in sub- 

 figure 2. By this time the stamen " bars," as I have called them, have 

 shrunken and become more or less twisted, so that there are mani 

 open spaces between them, as seen in 2a. Later the calyx lobes close 

 tightly and the " bars " shrivel still more, as seen in subfigures 

 and 3a. 



By reference to subfigures 2 and 3, it will be seen that there are tw 

 distinct cavities at first, one above and one below the stamens, eithei 

 of which might be called the calyx cup, and which have been treate( 

 as a single cavity by most writers. 



