THALAMIFLOR^ i6i 



i8. The Flax Group. 



The Common Flax has been selected as a type of 

 the Order Linaceae. Four species of Flax are found 

 in the British Isles, and also All-seed, or Radiolay 

 which differs from Flax in having the parts of the 

 flowers in fours, not in fives. 



Of this order about one hundred and twenty 

 species have been recognised, placed in nine genera. 

 In distribution they are more or less cosmopolitan. 

 The Flax group shows affinity with the Mallow and 

 Geranium groups, and also with the foreign groups, 

 Malpighiaceae and Ternstroemiaceae. From the 

 Geranium group it is distinguished by the foliage 

 and absence of a carpophore, and from the Pink 

 group, which it resembles in habit, by the pin-headed 

 stigma and fruit. 



The Flax group consists of herbaceous plants, 

 undershrubs or trees. The leaves are alternate, 

 nearly opposite, simple, entire, without stipules as a 

 rule. 



The flowers are regular and hermaphrodite, the 

 inflorescence cymose. The parts are usually in fives. 

 The calyx is polysepalous, inferior, with four or five 

 sepals, quincuncially arranged, distinct, or rarely 

 united below, persistent, overlapping in bud. The 

 corolla is polypetalous with four or five petals, 

 twisted in the bud or overlapping, soon falling. The 

 stamens are five, or twice as many, or more, alternate 

 with the petals. Some staminodes, or functionless 



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