combined growth of both parents. Many tremen- 

 dous growers are got in the first generation, but in 

 the second there are included some of the most 

 rapidly growing trees, perhaps, in the world. This 

 hybrid has clean-cut, glossy bright green leaves 

 from two to three feet long with a sweet odor like 

 that of apples, but it produces few nuts. Curiously 

 enough the result of hybridization by using the 

 pollen of nigra on pistils of calif ornica produces in 

 abundance large nuts of a quality superior to that 

 possessed by either parent. 



The famous Shasta daisy is the result of a mul- 

 tiple crossing between an American and a Euro- 

 pean species of field daisy and then between' these 

 hybrids and a Japanese form. The fragrant calla^ 

 known as 'Fragrance,' is decended from a single 

 individual found by Burbank while critically ex- 

 amining a block of Little Gem calla seedlings. 

 He was surprised in this examination by a fragrance 

 resembling that of violets or water-lillies ; as he 

 had long been seeking a fragrant calla, the indivi- 

 dual giving this perfume was carefully handed out. 



109 



