THE STORY OF SOME COMMON PLANTS?. 143 



perhaps show that these species are made up of a large number of 

 varieties which produce themselves " true ' from seed. 



New Zealand flax grows in most diverse stations, and the structure 

 of its leaves probably varies much according to environment. Faces 

 of dry cliffs, clayey hillsides, swamps, and sandhills are some distinct 

 spots where P. tenax flourishes. Nor is it fastidious as to climate. 

 The warm valleys of northern Auckland, the wind-swept shores of 

 south AVestland, the bleak moorlands near Inveicargill. the quaking- 

 bogs of the Chatham Islands, all afford it a suitable home. This 

 Chatham Island form is distinct from the typical variety, its leaves 

 being thinner, broader, and drooping, and its fibre comparatively 

 weak, but very fine. There is also a small amount of flax on the 

 Auckland and Campbell Islands ; but it is not indigenous, having 

 been planted there by the Maori sealers many years ago. 



The flowers of the flax are not verv showv. being of a lurid red in 



/ / * o 



P. tenax and yellow in P. CooJcianum. The pollen is usually ripe before 

 the stigma of the same flower is ready to receive it. a fact which points 

 to cross-fertilisation as a possible cause of the great variation of the 

 species. The abundance of honey contained in the flowers attracts 

 the tui and other native birds, who assist in the work of fertilisation, 

 playing the part performed in many plants by insects. 



The leaves spring from a short but stout creeping stem, and this 

 latter, spreading over the ground, helps to increase the spread of 

 the plant. It grows readily from seed also ; and from the seed- 

 lings, if raised in a sufficient quantity, new varieties might be 

 expected. 



The leaves are stout and thick, and stand erect, thus avoiding the 

 direct rays of the sun a contrivance against loss of water, as shown 

 before. That a swamp plant should require protection against drought 

 seems absurd, but this special drought-combating structure it is which 

 permits the plant to inhabit rocks, dunes, and other excessively dry 

 stations mentioned above. Nor does it seem unlikely that the flax 

 has been driven into the swamps by its competitors, and lives there 

 not from choice, but from necessity, though its drought-resisting 

 structure is no longer an advantage, unless the water of the swamp 

 be acid.* 



* See remarks on physiological dryness in Chapters V and VII. 



