FRUITS FROM THE TROPICS 291 



My experiments were promising at the outset, 

 and I soon had a variety of hybrid seedlings. 



But there came a series of cold winters that 

 destroyed the entire citrus orchard, and after 

 one or two other tentative efforts, I was com- 

 pelled to admit that my farms are located in a 

 region unsuited for development of the citrus 

 fruits. The initial investigations through which 

 the hardy orange is developed must be made in 

 a more favorable locality. 



I frequently mentioned my belief that a hardy 

 orange could be developed, however, and it is 

 satisfactory to record that experiments along 

 this line have more recently been undertaken 

 under the patronage of the United States 

 Government. 



The variety known as Citrus trifoliata, a wild 

 form which had never been much cultivated ir 

 America, was known to be exceptionally hardy 

 This was hybridized with the sweet orange in the 

 Government experiments just referred to, and 

 the early results were thought to be rather 

 promising. 



"Among the seedlings observed/' says Profes- 

 sor E. M. East, "several have proven valuable. 

 They form a new class of citrus fruits and have 

 been called Citranges. Three of these varieties 

 have been named the Rusk, the Willits, and the 



