1882.] 



and Cassia t 



2S5 



In gathering the pollen, some grains are dropped on the in- 

 curved petal, and by it made to adhere to parts of the bee, and to 

 such parts in a right-handed flower as will carry it to the stigma 

 of a left-handed flower, and vice versa. 



So much for the observations upon the plants themselves. Let 

 us trace their more marked peculiarities in related plants, and, if 

 possible, find some hint as to their origin. 1 



In Solanum rostratum the particulars in which it differs from 

 the normal form of the genus, are three, viz: (1) The long re- 

 curved style ; (2) the elongation and enlargement of the lower 

 stamen ; and (3) the crooking of them toward opposite sides of 

 the flower. In examining kindred species of this most numerous 

 genus, we find that in our common S. nigrum in Southern California, 

 there appears a variety, S. Dillenii, which 5 



exerted, and 

 Another, S.^nodiflor- 

 um t in Arizona, which 

 " generally has this 

 feature," passes into 

 S. Douglassi which is 

 found at Santa Bar- 

 bara, Cal. The de- 

 velopment of this char- 



and perhaps depends 

 upon, the change 

 of the flowers from a 

 drooping attitude, as 

 in the typical nigrum, 



lias 



to ; 



:rect posi- Fig. 3.— «, 

 obliquity , 



/>.•::.-» 



■ d, flower 



of the 

 their vertical asym- 

 metry, as it might be called, appears in S. tuberosum sometimes. 

 I have observed it in the "peach-blow" variety; I have observed it 

 more frequently in S. Carolinensc. The extreme form, however, 

 which we have found in 5. rostratum, is confined to the sub- 





1 ™ r >" ■' 



