GROWTH OF PLANTS INDEPENDENTLY OF SEEDS 61 



nodes, and as the internodes decay, a new plant is formed at 

 each node that has developed adventitious roots. This is one of 

 the most prolific of the Meadow Buttercups, and is therefore 

 easily observed. The Ground Ivy, very common in hedges, 

 propagates itself in a similar way. Two weeds that are very 

 troublesome to the farmer, and which would cover large areas of 

 ground if left alone, spread in this way, namely, the Creeping 

 Plume Thistle and the Couch-Grass. It is no use cutting off the 

 heads of the thistle, as the underground stem is perennial and 

 creeps along underneath the ground. The couch-grass forms 

 buds in the axils of the leaf-sheaths, the buds burst through the 

 sheath and run horizontally as underground stems, called stolons. 

 These root as they creep along, forming new plants at each rooting. 

 Although some grasses are a nuisance to the farmer, others are 

 of value, especially on sandy shores. The two most important are 

 the Sea Mat-Grass (Psamma arenaria) and the Sand Lyme Grass 

 (Elymus arenarius). Neither of these is of any use as fodder, but 

 they bind sand together, and help to build up sand-dunes. This 

 is very well seen at a place like Newbiggin-on-Sea, not far from 

 Newcastle. The sand on the seashore is blown about by the wind, 

 and may be described as shifting sand ; here the grasses begin 

 their work of binding, and a few yards inland the shifting sand 

 gives place to a region of firmer sand, where sand-dunes are being 

 formed. In passing, it may be mentioned that the vegetation 

 of the shifting sand area is far more scanty than that of the firmer 

 region, for until the grasses have done their work, it is impossible 

 for many other plants to get a sufficient depth of soil in which 

 to grow. 



The common Cinquefoil (Potentilla reptans\ which is found 

 in most hedges and on waste ground, has stolons with long inter- 

 nodes. On examining these stolons, it will be found that each 

 is made up of a number of branches, for at each node there is a 

 reduced leaf, in the angle of which a new stolon-branch originates ; 

 each new branch continues the direction of growth of the pre- 

 ceding branch, giving the appearance of one long continuous 

 stolon. 



This creeping habit of plants has been made use of in cultiva- 

 tion. The Solomon's Seal and Iris of our gardens are perpetuated 



