70 Karl M. Wiegand and Arthur J. Eames 



11. Cynosurus L. 

 1. C. cristatus L. Dog's Tail Grass. 



Roadsides and grassland, in rich soil ; rare. June-July. 



E. of Cascadilla Place, Ithaca (£>.) ; C. U. campus, e. of reservoir, 1914 (C. C. 

 Thomas) ; Newman corner, Cayuga Heights, 1917; Wright lot, Upland Road, Cayuga 

 Heights, 1920; doubtfully established. 



Newf. to Ont., N. J., and N. Y. Adventive from Eu. 



Tribe 2. Hordeae 



12. Agropyron Gaertn. 



a. Plants with creeping rootstocks ; spikelets 3-7-flowered, loosely appressed to the 



axis of the spike. 1. A. repens 



a. Plants without creeping rootstocks, more cespitose; spikelets 2-4-flowered, more 

 closely appressed, and with thinner glumes. 2. A. caninmn 



1. A. repens (L.) Beauv. Quack Grass. Couch Grass. 



Roadsides, cultivated fields, and gardens, in various soils ; very common. Jul}'. 

 Range throughout N. A. except in the extreme North. Naturalized from Eurasia. 

 A pernicious weed, spreading rapidly by rootstocks. The awned form is especially 

 frequent around salt springs. 



2. A. caninum (L.) Beauv. 



Dry banks and cliffs, in neutral or slightly acid soils ; infrequent. July. 



Caroline Pinnacles ; Thatcher Pinnacles ; hill near Slaterville Swamp ; Enfield 

 Glen ; ravine n. of Lake View Cemetery ; Fall Creek, above Forest Home ; Renwick 

 Road, Cayuga Heights ; near Esty Glen ; Taughannock Gorge, cliffs near the falls ; 

 Lowery Ponds. 



Lab. to B. C, southw. to N. C, Wis., Nev., Ariz., and Calif. ; rare on the Atlantic 

 Coastal Plain. 



Sheaths and blades glabrous, or with a varying amount of pubescence (forma 

 pubescens (Scribn. & Sm.) Pease & Moore). According to Pease and Moore 

 (Rhodora 12:61. 1910), the awns of the typical form are 7-15 mm. long. Plants 

 with awns less than 6 mm. long are referred to var. tenerum (Vasey) Pease & 

 Moore, and those with awns 1.5 cm. long or more, to var. unilaterale (Cas.) Vasey. 

 These various forms occur in the Cayuga Lake Basin. 



13. Lolium L. 

 a. Empty glume equaling or exceeding the upper flowering glume; rhachis of the 

 spike at middle 2-2.8 mm. wide; culms at base 2-3 mm. in diam. 



1. L. temulentum 



a. Empty glume equaling the upper flowering glume or shorter ; rhachis of the spike 

 at middle 1.5-2 mm. wide; culms at base 1-2 mm. in diam. 

 b. Flowering glumes awnless ; rhachis of the spike with sides smooth, angles 

 scabrous ; empty glumes 5-nerved ; leaves conduplicate. 

 c. Plants perennial, with tufted basal leaves ; spikelets 5-8-flowered. 



2. L. perenne 



c. Plants annual probably, coarser and taller, generally without tufted basal 

 leaves ; spikelets 10-14-flowered. 2a. L. p., var. orgyiale 



b. Flowering glumes short-awned; rhachis of the spike with sides as well as angles 

 finely scabrous ; leaves convolute. 

 c. Empty glumes 7-nerved ; spikelets 10-20-flowered ; plants coarse, annual, rarely 



with clustered basal leaves. 3. L. multiflorum 



c. Empty glumes narrower, 5-nerved; spikelets 5-10-flowered ; plants usually 

 perennial, sometimes with clustered basal leaves ; empty glumes more 

 conspicuous. 3a. L. m., var. diminution 



