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

 sail d- binders. 



"With intra-vaginal branches only. 



Loliam — slightly stoloniferous. 



Festuca elatior— slightly stoloniferous. 



Avena flavescens — slightly stoloniferous. 



Phleum pratense — no stolons, but may be bulbous. 



Dactylis — no stolons. 



Festuca ovina— no stolons. 



Foa alpina — no stolons. 



Cynosunis— wo stolons. 



With extra- vaginal shoots. 



Arrlienatherum — short stolons, sometimes bulbous. 

 Holcus ^an«^i«s— creeping. 

 Alopecurus pixitensis — long stolons. 

 A n thox'tinthum — slightly stoloniferous. 

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

 Digra.phis — long stolons. 

 Foa pratensis — long stolons. 

 F. tHvialis — runners only. 



Festma heterophyUa^ Lam.— a variety of F. ovina with sliglit 

 stolons. 



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

 Bromus erectiis — no stolons. 

 B. inermis—low'j' stolons. 



