596 THE AMERICAN NATURALIST [Vol. XL VIII 



subject have been collected by Munson, 3 who found that 

 evidence that the pollen has any direct effect upon the 

 fruit is largely lacking. Aside, then, from indirectly 

 modifying the size of the fruit, the influence of the pollen, 

 in so far as our present knowledge goes, may be left out 

 of account in a study of apple variation. 



Without doubt the most noteworthy contributions to 

 the knowledge of apple variation are the recent papers 

 by Shaw, of the Massachusetts station, and Stewart of the 

 Pennsylvania station. Shaw's first paper, which ap- 

 peared in the Massachusetts station report for 1910, deals 

 entirely with the variation of the Ben Davis apple. In 

 comparing specimens grown in a number of widely sepa- 

 rated localities it was noted that variations due to cli- 

 matic condition were strongly marked and affected prac- 

 tically all characters of the fruit. Modifications of form 

 were especially noticeable The depth of coloration was 

 looked upon as correlated with latitude, being pink in the 

 specimens from Arkansas and deep crimson in those 

 grown farther north. The amount of overcolor seemed 

 to be controlled by local conditions. The color was espe- 

 cially good in the apples from the Pacific coast and those 

 from Colorado, Pennsylvania, and Indiana. In a given 

 orchard temperature appears to be the most influential 

 factor governing size. The flesh was notably white in the 

 fruit from Colorado. The apples from Colorado and 

 California were less firm than those from other localities. 

 The southern-grown specimens were more juicy and of 

 better quality than those from the north, which were apt 

 to be dry, hard, flat, and sometimes astringent. It ap- 

 pears that a mean temperature of at least 60° F. for the 

 growing season is required for the satisfactory produc- 

 tion of the Ben Davis. The poor quality of the northern- 

 grown specimens is apparently due to a lack of sufficient 

 heat to properly develop the fruit. 



In Shaw's second paper in the Massachusetts station 

 report for 1911 the fact is emphasized that the grower 



s Me. Sta. Eept. (1892), pp. 29-32. 



