12 



BRANCHING 



[CH. 



ing shoots. The buds always arise in the axils of the lower 

 leaf-sheaths — i.e. they are intra-vaginal. If they remain 

 intra-vaginal during further growth, the shoots are forced 

 upwards and only tufts (Fig. 2) are formed, except in so far 

 as such shoots may fall prostrate on the surface of the 

 ground later, and throw out roots from their nodes, and 

 so act as runners or offsets, or put out a few roots &c. 

 as they ascend through the soil. But in many cases the 

 buds soon burst through the leaf-sheaths, and develope 

 as extra-vaginal shoots, and may then run horizontally 

 as underground stolons. Only creeping grasses of these 

 latter kinds can rapidly cover large areas ^: the grasses 



Fig. 4. Catabrosa aquatica. Plant showing the creeping habit, rooting 

 nodes, and paniculate inflorescence (reduced). Paruell. 



' Except, of course, in cases of virgin ground rapidly occupied by the 

 seedlings. 



