1913] Reports on the Flora of the Boston District,— XVIII 145 
1888, cannot be traced, and hence the reference cannot be verified. 
They doubtless all belong to other species.] 
P. annua L. Waste places, abundant throughout. 
P. compressa L. Waste places, fields and woods, in dry and moist 
soil. Common throughout. 
P. NEMoRALIS L. Wenham (J. Robinson, July 4, 1875); Percival 
St., Dorchester, introduced (J. R. Churchill, June 26, 1898). The 
Wenham plant was also probably an introduction. 
P. pratensis L. Fields and meadows, common throughout. 
P. triflora Gilib. Dry and wet ground, common throughout. 
P. rriviatis L. Damp ground and waste places. Fairly well 
distributed but not common, from Dedham and Hingham northward. 
GLYCERIA. 
G. acutiflora Torr. Wet boggy places and in shallow water. 
Fairly common throughout. 
G. borealis (Nash) Batchelder. Wet places and in shallow water; 
Boxford, Stoneham, Malden, Needham and Natick. 
G. canadensis (Michx.) Trin. Low ground, common throughout. 
G. grandis Wats. Wet places. Fairly common in northern half 
of district, probab!y found throughout. 
G. laxa Scribn. West Gloucester (F. T. Hubbard, Sept. 27, 1911, 
specimen in herb. F. T. Hubbard); Reading (W. H. M anning, July 8, 
1882, specimen in herb. N. E. Botanical Club). 
G. melicaria (Michx.) Hubbard. (G. Torreyana (Spreng.) Hitche.; 
see Hubbard, Ruopora xiv. 186, 1912.) Essex Co. (W. Oakes, no 
date); bank of brook near Merrimac River, East Haverill (J. H. Sears, 
Sept. 11, 1901); Brookline (S. Harris, June 27, 1894). Also observed 
but not collected in Weston and Dedham, July, 1908, by K. M. 
Wiegand. 
G. nervata (Willd.) Trin. Swamps and low ground, common 
throughout. 
G. obtusa (Muhl.) Trin. Borders of ponds and wet ground. Well 
distributed throughout, and fairly common. 
G. pallida (Torr.) Trin. Shallow water. Seventeen stations from 
Sudbury eastward. 
G. pallida (Torr.) Trin., var. Fernaldii Hitchc. Edge of pond, 
Woburn (C. H. Knowlton, June 20, 1908); ditch, Concord (W. Deane, 
