EATONIA ELYMUS 351 



EATONIA Rafinesque 1819 EATONIA 



(Named for Eaton, an American botanist) 



PI. 45, fig. 30. 



Spikelets 2-3-flowered, in narrow panicles, the axis extended beyond 

 the flower; glumes unequal, the lower linear, acute, 1 -nerved, the upper 

 much broader, obtuse or rounded, 3-nerved, the edges papery ; lemma lance- 

 olate, usually obtuse, palet narrow, 2-nerved; perennial. 



1. Panicle dense and spike-like, the branches 1-1.5 



in. long ; upper glume obovate, almost truncate E. obtusdta 



2. Panicle loose, the branches 1-2.5 in. long, upper 



glume oblanceolate, ^ obtuse to acutish E. pennsilvdnica 



ECHINOCHLOA Beauvois 1812 BARNYARD GRASS 

 (Gr- e chinos, hedge-hog, chloe, grass, from the spiny spikelets) 



Spikelets 1-flowered, in 1-sided racemes which are again grouped in 

 racemes or panicles ; glumes 2, the upper awned or awn-pointed, a sterile 

 awned lemma, the lemma and palet enclosing the perfect flower ; broad-leaved 

 annual. 

 Stems 1-4 ft. high; panicle of 5-15 branches; sterile 



lemma with a long or short awn E. crus-gdlli 



IILYMUS Linne 1753 WILD RYE 



(Gr. elymos, rolled up, from the inrolled palet) 



PI. 46, fig. 24. 



Spikelets 1-6-flowered, usually in pairs in a dense terminal spike, alter- 

 nating on the joints of the axis, the glumes forming a sort of involucre for 

 the cluster ; glumes awl-shaped, acute or awned ; lemma rounded, 5-nerved, 

 usually awned, palet 2-keeled ; perennial. 



1. Awns spreading widely ; joints of the axis separ- 



ating from each other readily at maturity E. sitdnion 



2. Awns erect or ascending, or none ; joints of the 



axis not separating readily at maturity 

 a. Lemma conspicuously awned 



(1) Spikelets spreading from the axis of the 



broad spike ; glumes with awns 16-32 

 mm. long; awn of the lemma 2-5 cm. 

 long E. canadensis 



(2) Spikelets appressed to the axis of the nar- 



row spike ; glumes 8-12 mm. long, short- 

 awned or awn-pointed ; awn of the lem- 

 ma 1-2 cm. long, or less E.sibiricus 



