192 The Cross Ponination of Flax 



to assume that the pollen lived and gave some stimulus to the carpels 

 but failed owing to some morphological or chemical obstacle to reach 

 the ovules. Such stimulation of the ovaries without fertilisation is 

 known to occur in other orders of plants. 



In 1914 renewed attempts were made to fertilise the yellow flaxes 

 by pollen from flaxes containing enzymes and glucosides. In the case 

 o{ L. arburenm (Linn.), a species which resembles L. flavum (Linn.) but 

 differs by its shrubby habit, more woody stem and its glaucous leaves, 

 two hundred trials were made with pollen from L. inonogyrium (Forst.), 

 upwards of one hundred trials with pollen from L. narhonennse (Linn.), 

 fifty trials with L. austriacum (a variety of L. pereiine) and one hundred 

 and fifty trials with blue flowering L. perenne, and in no case was any 

 positive result obtained. Although the stigmata remained perfectly 

 healthy no .swelling of the ovaries took place. Attempts were made again 

 to effect a cross between L. fluvuvi (Linn.) and L. monogynum (Forst.), but 

 in none of the one hundred and fifty trials made did fertilisation of the 

 L. flavum take place and fifty attempts to effect the reciprocal cross, 

 L. monogynum $ with L.Jlavuni (/", only gave one capsule containing 

 one seed which did not germinate. Our efforts to fertilise L. narhonennse 

 by i. monugynum and by L. arboreum were no more successful and more 

 than one hundred trials to pollinate blue L. perenne by L. arboreum and 

 by L. monogynum were equally unsuccessful. Similarly when white 

 flowering L. perenne and L. austriacum were employed for pollinating 

 L. arhoreiiin no fertilisation ensued. The pollination of L. monogynum 

 by L. arboreum appeared at first to have been successful ; most 

 of the two hundred trials made resulted in early swelling of the 

 ovaries and capsule development set in, but after about three weeks all 

 but three capsules had dropped off and of those which remained one 

 contained no seed, one contained ten seeds and the other three seeds. 

 From these eleven plants have been raised, the foliage of which 

 resembles that of L. monogynum both in general appearance and in 

 containing both enzyme and glucoside associated with that species. 

 So far these plants have shown no signs of flowering, and in this 

 respect they differ from seedlings of L. monogynum raised at the same 

 time. 



Some two hundred trials were made to secure a cross between 

 L. monogynum % and L. narhonennse </ and of these quite half 

 exhibited swelling and the capsules remained on the plant for some 

 time. Finally however only three capsules remained and these yielded 

 two and three seeds in each. From these only three plants could be 



