10 



CONTENTS. 



XV. 



XVI. 

 XVII. 



XVIII. 



XIX. 

 XX. 



XXI. 



XXII. 

 XXIII. 

 XXIV. 



Page 

 A Pomological Alliance. Sketch of the Relation- 

 ship between American and Eastern Asian 



Fruits 267 



Horticultural Geography 278 



Some Emphatic Problems of Climate and Plants. 

 Comprising " Speculative Notes upon Phenol- 

 ogy (the Physiological Constant, and the Cli- 

 matal Modification of Phenological Phenom- 

 ena) ;" and "Some Interrelations of Climatology 



and Horticulture" 288 



Are American Fruits Best Adapted to American 



Conditions ? 311 



Acclimatization: Does it Occur? 320 



On the Longevity of Apple Trees 334 



Sex in Fruits 347 



Are Novelties Worth their Cost? 356 



Why Do Promising Varieties Fail? 364 



Reflections upon the Longevity of Varieties, 

 Comprising "Do Varieties Run Out?" "Are 

 the Varieties of Orchard Fruits Running Out?" 

 "Studies in the Longevity of the Varieties of 

 Tomatoes" 376 



PART III. 



Essays Tracing the Evolution of Particular Types of 

 Plants. 



Page 

 XXV. Whence Came the Cultivated Strawberry? .... 400 



XXVI. The Battle of the Plums 418 



XXVII. The Evolution of American Grapes 431 



XXVIII. The Progress of the Carnation. Comprising 

 " Types and Tendencies in the Carnation ; " 

 "John Thorpe's Ideal Carnation;" and "Bor- 

 der Carnations" 438 



XXIX. Evolution of the Petunia 465 



