MIDDLESEX FLOKA. 127 



S. vaginaeflorus, Vasey. (Vilfa vaginaeflora, Torr., Man.) 

 Not uncommon. 



Agrostis, L. 



A. perennans, Tuck. Thin Gr4.ss. 



Lowell and Hopkinton (Dr. C. W. Swan) ; Maiden (E. Prohock) ; 



Winchester (C. E. Perkins) ; Concord (E. S. Hoar). 

 A. scabra, Willd. Hair Grass. 



Common. 

 A. canina, L. Brown Bent Grass. 



Medford (Miss A. M. Symmes) ; Woburn (Wm. Boott) ; Concord 



(E. S. Hoar). Not common. 

 A. alba, L. White Bent Grass. 



Common. Naturalized here, but native farther north and west. 

 A. alba, L., var. VULGARIS, Thurb. (A. vulgaris, With., Man.) Rep- 

 Top. 



Common. Nat. here, like the type. 



POLTPOGON, Desf. 

 P. Mon^eliensis, Desf. Beard Grass. 



Lowell, Billerica and Dracut (Dr. C. W. Swan) ; N. Chelmsford 



(Kev. W. P. Alcott) ; near woollen mills. Adv. from Eu. 



CiNNA, L. 



C. arundinacea, L. Wood Beed Grass. 

 Concord, Westford, Arlington, et al. Occasional. 



C. pendula, Trin. (C. arundinacea, L., var. pendula, Gray, Man.) 

 Ashby (Dr. C. W. Swan) ; Waltham List. 



Gastridium, Beauv. 

 <jf. australe, Beauv. 

 Lowell and Billerica, in wool waste (Dr. C. W. Swan). Native of 

 Eu., but probably adv. here from Cal., where it is naturalized. 

 "Panicle contracted into a somewhat loose, tapering spike, 

 spikelets 1-flowered. Glumes with an enlarged, ventricose, shining 

 base, very acute above, obscurely keeled, the lower longer. Floret 

 less than one-fourth the length of the lower glume, having a very 

 short callus, which is clothed with minute hairs. Lower palet very 

 thin, truncate and dentate at apex, just below which is a very 

 slender awn, equalling or exceeding the glumes (or sometimes 

 absent) ; upper palet equalling the lower. Scales two, linear, as 

 long as the ovary." Bot. Cal. 



Deteuxia, Clarion. 



D. Canadensis, Hook. (Calamagrostis Canadensis, Beauv., Man.) 

 Blue Joint Grass. 



Common. 



