l] STOLONIFEROUS GRASSES 13 



with intra-vaginal shoots only can only make tufts or 

 " tussocks.'' Several peculiarities in the habits of grasses 

 depend 'on these facts. The following are the most 

 important creeping, or stoloniferous species, contrasted 

 with the much more common tufted and the far rarer 

 grasses with runners above ground (Fig. 4). Some of 

 these {Elymvts, Psamma, &c.) are of great importance as 

 sand-binders. 



With intra-vaginal branches only. 



Lolium — slightly stoloniferous. 



Festuca elatior— slightly stoloniferous. 



Avena Jlavesoens — slightly stoloniferous. 



Phleum pratense — no stolons, but may be bulbous. 



Dactylis — no stolons. 



Festuca ovina — no stolons. 



Poa alpina — no stolons. 



Gyrwswrus — no stolons. 



With extra-vaginal shoots. 



Arrhenatherum — short stolons, sometimes bulbous. 

 ffolciis lanatus— creeping. 

 Alopecunis pratensis — long stolons. 

 Anthoxanthum — slightly stoloniferous. 

 Agrostis alba (var. stolonifera) — long stolons and runners. 

 Digraphis — long stolons. 

 Poa pi-atenns — long stolons. 

 P. trivialis — runners only. 



Festwea heterophylla. Lam. — a variety of F. ovina with slight 

 stolons. 



F. rubra (Linn.) — a variety of F. ovina with long stolons. 

 Bronvm erectus — no stolons. 

 B. inermis — long stolons. 



