472 BOTANY OF CROP PLANTS 



is loosely cymosc. The llowers vary in color from while to 

 deep blue. The same plant always bears llowers of the 

 same color. Yellow-flowered varieties are not found in 

 this species. The [)etals are large, conspicuous, wedge- 

 shaped, and about twice as long as the sepals. 



Pollination.— Studies of flax varieties indicate that there 

 is close-pollination. Individual flowers produce seed freel\-, 

 whether associated with other flowers or not. Examination 

 of'^flax llowers_ at the proper time shows anthers in close 

 proximity to the stigmas, and the latter covered with pollen. 



Mature Fruit. — The flax fruit (Fig. 21) is a round capsule 

 known commercially as the "seed ball." The seed ball is com- 

 posed of live fused carpels. The balls are divided into li\e 

 true ca\ities or locules by means of live true partitions (sei)ti) 

 extending from the wall (pericarp) to the axis. Each loculc 

 contains two seeds and is divided more or less incompletely 

 into two loculi by means of false septi. The seed balls are 

 yi inch or more in diameter. When fully ripe, they are 

 easily separated into parts at the points where the car[)els 

 are joined. 



Seeds. — The seeds vary in length from \i to '- inch. 

 They are lenticular, compressed, and slightly longer than 

 wide. They have a very smooth, pohshed surface and vary 

 in color from yellow to dark brown. Light brown is the 

 standard color. A mucilaginous material which quick I \- 

 becomes sticky (viscid) in hot water is found tilling the 

 epidermal cells of the seed. It is this substance which gives 

 flax its medicinal value. The embryo is surrounded by a 

 thin layer of endosperm which, in the mature seed, contains 

 starch. 



Geographical. ComnKju flax is a mitivc of Eiiropi;. IL is now widely tlis- 

 IribiiLcd over the world, hiring grown commercially in m;iny countries. Jndi;i 

 is a heavy producer of seed, and in Argentina it is grown extensively for oil. 



