190 The Cross Follumtioii of Flax 



The flowers of all the flaxes so far examined— numbering more than 

 sixty — are hermaphrodite and although the flowers are slightly pro- 

 tandrous, when attempting to cross-fertilise it was found necessary to 

 emasculate the buds. 



The petals fall very readily when the buds are opened for the 

 removal of the stamens. This of course deprives the stigmata of their 

 protection, but seems to be in no way detrimental. It was found 

 convenient therefore to discard the usual method of emasculation for 

 the following. When the bud is advanced to within a day or so of 

 opening, the tijjs of the petals were taken between the finger-tips and 

 the corolla removed by a sudden jerk, thus exjjosing the stigmata and 

 at the .same time eff'ecting the complete removal of the stamens. The 

 stigmata, which at this stage are not receptive, apparently suffer no 

 more by this somewhat rough treatment than by the more careful 

 method usually employed ; the bag by which they are covered affording 

 sufficient shade and retaining the necessary moisture for their normal 

 development, and we were able to convince ourselves by numerous 

 trials that the stigmata were not pollinated by the removal of the 

 stamens by this methods 



Whilst testing the efficacy of this rough method of emasculation, a 

 large number of flowers were so treated and kept covered without being 

 pollinated. In every case the stigmata dried off and no sign of 

 capsule development could be detected. This fact is recorded as 

 showing that in the three species so treated, namely L. perenne, 

 L. jiavum and L. maritimum, seed is not n(jrmally produced partheno- 

 genetically. 



The flowers of some species of Linum, like those of the primrose, 

 have styles of two different lengths, i.e., are dimorphic. This 

 dimorphism is considered to be an adaptation favouring cross fertilisa- 

 tion and has been referred to by Darwin and others. Darwin- records 

 that L. perenne yields no seed as a result of illegitimate jwllination : 

 we have not been able to confirm this but have found that when using 

 this species of Linum about 30 j)er cent, of the short styled flowers 

 produced seed capsules when " covered " owing to the pollen dropping 

 on to the stigmata and very few of the long styled flowers set seed 

 under the same conditions of isolation. It is probable that both types 



^ After some practice it was found possible to use this method of emasculation success- 

 fully with long styled as well as short styled flaxes. Some care has to be exercised 

 however in selecting buds in which the style has not become too elongated. 



- Furms of Flowers, 1892, p. 89. 



