Ijr SEVKBAI SPECIES OP THE OE\rs LI^-rM. 71 



two plants produced, before and after and at tlie time of tlic trin], 

 a vast number of flowers, but the germens of not even one swelled. 

 All these flowers, thougb their stigmas were so densely covered 

 with their own pollen, were absolutely barren. 



The nine other plants, six long-styled and three short-styled, 

 grew in the beds of the same flower-garden. Four of the long- 

 styled produced no seed-capsules ; one produced two ; but the re- 

 maining long-styled plant grew so close to a short-styled plant 

 that their branches touched, and this produced twelve capsules, 

 but they were poor. The case was dift'crent with the short-styled 

 plants. The plant which grew in juxtaposition with the long- 

 styled plant produced ninety-four imperfectly fertilized eapsides 

 containing a multitude of bad seeds, with a moderate number of 

 good seeds. The two other short-styled plants grew in a single 

 clump, and were very small, being partly smothered by other 

 plants ; they did not stand very close to any long-styled plants, 

 yet they yielded together nineteen capsules. These facts seem to 

 show that the short-styled plants are far more fertile with theijr 

 own pollen than the long-styled. We shall immediately see that 

 this is the case in a slight degree. But I suspect that in tin's 

 instance the difierence in fertility between the two forms was in 

 part due to a distinct cause-. I repeatedly watched the flowers, 

 and only once saw a humble-bee momentarily alight on one, and 

 then fly away, as if it were not to its taste. If bees had visited 

 the several plants, there cannot be a doubt that the four long- 

 styled plants w"hich did not produce a single capsule would have 

 borne an abundance. But several times I saw small diptera suck- 

 ing the flowers ; and these insects, though not visiting the flowers 

 with anything like the regularity of bees, would carry a little 

 pollen from one form to the other, especially wlicn growing close 

 together; and the stigmas of the short-styled plants, diverging 

 within the tube of the corolla, would be more likely than the up- 

 right stigmas of the long-styled to receive a small quantity of 

 pollen when brought by small insects. l<'rom the much greater 

 number of long-styled than of short-styled flowers in the garden, 

 evidently the short-styled would bo more likely to receive some 

 pollen from the long-styled, than the long-styled from the short- 

 styled. 



In 1S62 I raised thirty-four plants of this Linum in a hotbed ; 

 and these consisted of seventeen long-styled and seventeen short- 

 styled forms. Seed sown later in the flower-garden yielded seven- 

 teen long-styled and twelve short-styled forms. These facts justify 



