The Grahhes of Tkwksskk. 61 



Scries B. POACE.E. 

 Spikelets one- to many- flowered, the imperfect or rudimentary 

 flower, if any, is usually uppermost; rachilla usually articulated 

 abovx the empty j^^lumes, so that these remain after the fall of the 

 fruiting glume. ^ In spikelets with two or more flowers, these are 

 separated by a manifest internode of the rachilla, and in such 

 cases the rachilla is usually articulated below each flowering 

 glume. 



Tribe VII. PII ALARIDE .V:. 



Spikelets more or less laterally compressed, one- or rarely three- 

 flowered. Glumes five, the first two empty and below the articu- 

 lation of the rachilla; the third and fourth above the articulation, 

 usually empty, very unlike the outer ones, rarely enclosing a stam- 

 inate flower, sometimes reduced to mere bristles; the fifth glume 

 with a one-nerved or nerveless palea and a hermaphrodite flower. 



A small tribe comprising six genera, with about sixty species of 

 comparatively little importance. Several of the species, Sweet 

 Vernal-grass and Vaniliagrass, are remarkable for possessing a 

 peculiar sweet fragrance due to their containing coumarin. Ca- 

 nary-grass is one of the best known members of this tribe. 



16. PHALARIS Linn. Sp. PI. 54 (i753j. 



Spikelets one-flowered, strongly flattened laterally and crowded 

 in a dense ovoid cylindrical or rarely interrupted spike-like panicle 

 (sometimes spreading in flower); rachilla articulated above the 

 first pair of empty glumes. Glumes five, awnless, the first two 

 empty, equal, boat-shaped, and usually winged on the keel; the 

 third and fourth empty, narrow-lanceolate or bristle form, closely 

 appressed to the fifth or flowering glume, which is hard and shin- 

 ing in fruit and closely envelops the grain and palea. 



Annual or perennial grasses, with flat leaves and densely-flow- 

 ered spike-like or capitate inflorescence. 



Species about ten, most abundant in Southern Europe. There 

 are two or perhaps three native North American species. One of 

 these, together with a species introduced from Europe, is found 

 within the State. 



I. Phalaris Canariensis Linn. Canary-grass. 



Plate XVIII. Figure 69. 



An erect annual, one to three feet high, with flat leaves and a 

 dense, ovoid panicle (head) about an inch long, empty glumes 

 with a broad, sharp keel, with a distinct green line within the 

 white, scarious margins. Third and fourth glumes small, scale- 

 like smooth. Fifth or flowering glume hairy. 



* Alopecurus, Cinna, S/mrtina. and HoJcu^ In this Series, have the rachilla articulated 

 below the first pair of glumes, and the spikelets fall off entire. 



