IN-PLTTEKCE OP FOLL-Elf. 123 



influence of the pollen of flowers on tranches of other 

 varieties growing in close proximity. White' Apples 

 have been colored when growing near red varieties, and 

 those having smooth skins have heen covered with russet 

 on branches that have been interlaced with those of rus- 

 set trees. That this cross-fertilization does not occur 

 every season, is due to the fact that self-fertilization is 

 the most natural and frequent in the flowers of the Apple 

 and kindred fruits, and further, when crossing does 

 occur, it is not to be supposed that the efEect will always 

 be sufiicient to change the color or other characteristics 

 of the fruit. 



In the many experiments that I have made for the 

 purpose of determining the extent to which the influence 

 of the pollen could be distinctly traced, I will only refer 

 to one which has recently been completed on plants, so 

 common that the merest tyro in gardening must not only 

 be acquainted with them, but can readily repeat my ex- 

 periments if they care to do so. I refer to the Shrubby 

 Abutilons, which come to us from South America, where 

 some of the species grow to a height of thirty feet. 

 Kearly all the species and varieties in cultivation bloom 

 freely either in the open ground or under glass, but pro- 

 duce seed, very sparingly, and some none at all, unless 

 artificially cross-fertilized. Another point in their favor 

 for testing the influence of pollen is, that the seed-pods 

 of the different species and varieties are quite various in 

 size and form, and any disturbing or foreign influence 

 can the more readily be traced to the pericarpic organs. 

 Among the twenty or more species and varieties in culti- 

 vation, I selected Santana and Boule de Neige as two 

 extremes in the way of varieties likely to be the best 

 for my experiments. These may be only varieties of the 

 same species, but from the form and color of these flowers 

 I am inclined to think that Santana is from A. venosum, 

 and Boule de I{eige from A. pulchellum. My plant of 



