254 



Eue Warming. 



most abundantly at the base, and therefore, numerous 

 branches proceed from a central point, which is the upper 

 end of the primary root. They may, in some cases — at 

 an}- rate as long as they are still short — be more or less 

 erect, with curved and rooting branches, but soon they lay 

 themselves upon the ground, spreading out in all directions 

 and rooting as aerial shoots, and in a comparatively short 

 time they may attain a length of 10 — 25 cm, or even more. 

 Ultimately many slender adventitious roots are thereby 

 fastened to the ground, and by this means vegetative pro- 



Fig. 11. C er ostium trigynum. 

 A runner (about 1 / 1 ). As far as to L, reckoned from the flower, the 

 foliage-leaves are fresh, then come dead foliage-leaves which subtend 

 small shoots. Two leaves have been magnified. (Iceland; C. H. Osten- 

 feld). (E. W.) 



pagation may take place (Fig. 11). The apices may be 

 curved slightly upwards and the leaves may be unilaterally 

 curved (Fig. 11). From these runners a few or several 

 flowering shoots rise into the air; their duration of life is 

 two years (Thekla Resvoll). Sometimes the shoots are so 

 richly branched and so closely interwoven that broad, but 

 low cushions may almost be formed. 



Cerastium arvense has erect or ascending long-shoots, 

 with short, sterile shoots at its base. It also develops plagio- 

 tropic shoots quickly, and the seedling may, under cultiva- 

 tion, develop, in the year of germination, a richly branched 

 shoot-system, with typical scale-leaf-bearing runners. It 

 mav be denselv branched at its base. 



