Chap. III. LINUM PERBNNE. 93 



pollen, and about 30 with pollen from another plant 

 belonging to the same form, and these 50 flowers did 

 not set a single capsule. On the other hand he ferti- 

 lised about 30 flowers with pollen from the long-styled 

 form, and these, with the exception of two, yielded 

 capsules, containing good seeds. 



It is a singular fact, in contrast with what occurred 

 in the case of L. grandiflorwm, that the pollen-grains of 

 both forms of L. pererme, when placed on their own- 

 form stigmas, emitted their tubes, though this action 

 did not lead to the production of seeds. After an 

 interval of eighteen hours, the tubes penetrated the 

 stigmatic tissue, but to what depth I did not ascertain, 

 lu this case the impotence of the pollen-grains on their 

 own stigmas must have been due either to the tubes 

 not reaching the ovules, or,. to their not acting pro- 

 perly after reaching them. 



The plants both of L. perenne and grandifloriim grew, 

 as already stated, with their branches interlocked, and 

 with scores of flowers of the two forms close together ; 

 they were covered by a rather coarse net, through which 

 the wind, when high, passed ; and such minute insects 

 as Thrips could not, of course, be excluded ; yet we have 

 seen that the utmost possible amount of accidental fer- 

 tilisation on seventeen long-styled plants in the one 

 case, and on eleven long-styled plants in the other, 

 resulted in the production, in each case, of three 

 poor capsules ; so that when the proper insects are 

 excluded, the wind does hardly anything in the way of 

 carrying pollen from plant to plant. I allude to this 

 fact because botanists, in speaking of the fertilisation 

 of various flowers, often refer to the wind or to insects 

 as if the alternative were indifferent. This view, ac- 

 cording to my experience, is entirely erroneous. When 

 the wind is the agent in carrying pollen, either from 



