ms 



GENETICS IN RELATION TO AGRICULTURE 



Habit in Sweet Peas. There are several distinct types of plant in the 

 sweet pea the origin of which may be definitely ascribed to mutation. 

 The first Cupid plant (Fig. 123a) appeared among plants of the tall, 



, 



FIG. 123. a, Cupid or prostrate, dwarf sweet pea; 6, bush or erect, tall form; c, Cupid X 

 bush Fi, the ordinary tall form (folded over in order to photograph). (From Bateson.) 



white-flowered variety, Emily Henderson, in 1893. The growers, C. 

 C. Morse & Co. of San Francisco, raised seven acres of the new variety 

 in 1895 and every plant was true to type. This mutation has since oc- 



ii. 



Fio. 124. Dwarf or Cupid sweet peas. /, ordinary or prostrate Cupid; II, erect Cupid, the 

 Ft double recessive from bush X Cupid. (From Bateson.) 



curred in a number of widely separated localities. The bush type also 

 originated as a mutation from the tall form. The investigations of 

 the factor relations of bush and Cupid sweet peas have been described in 



