io8 Mi'iitoirs Bcniicc /'. liisliof^ .^[iisciiiu 



Lemmas l(jnj,a'r llian hroail. ilic inari^^ins claspiiiL; tlic jialca : ll<irct> iu>l lioiizcjntally s]>rL'aiIint;'. 

 Lemmas keeled on tlie back. 



Spikelets strongly comprcssfd, crowded in one-siilctl clusters at the ends of tiie 



stiff, naked ])aniclc brandies 8. Dactvlis (p. 1.^7) 



Spikelets not stroni^jly compressed, not crowded in one-sided clusters. 



Lemmas awned from a minutely bifid apex ( awnless or nearly so in Bromns 



iiiiioloidcs) : s])ikelets Iarf,fe 2. Bromus (p. hi) 



Lemmas awidess; sjiikelets small 5. Po.\ (]). 117) 



Lemmas rounded on tlie back, sometimes sli^btly keeled toward tlie summit. 



Xerves of the lemma parallel, not converj^^ing at the summit or but sliglitly so; 



lemmas awnless. mostly obtuse 4. P.vnicularia (p. 116) 



Nerves of the lemma converging at the summit ; lemmas awned or pointed. 



Lemmas entire, awneil from the ti]i or ix)inted 3. Festuca (p. 115) 



Lemmas awned or awn-tipped fmrn a ninmteiy bifid a])ex..2. Bromi's (p. hi ) 



HORDEAE. 



Spikelets more than i at each node of the rachis 9. HordiU'm (p. 139) 



Spikelets solitary at each node of the racJiis. 



Spikelets several-flowered in Hat spikes to. Ldlu'M (p. 139) 



Spikelets i-fiowered in cylindric spikes 11. Lupti-'RUS (p. 141) 



AVENEAE. 



Florets 2, one ])erfect. the other staininate. 



Lower floret staminate. the awn twisted, geniculate, exserted..i4. .\khiii:.v.\therum (p. 143) 



Lower floret perfect, awnless; awn of up|jer floret hooked 17. Xoriioi.crs (p. 147) 



Florets 2 or more, all alike e.xcept the reiluced upper ones. 



Spikelets large, the glumes over i cm. long 13. .\\i:n.\ (p. 142) 



Spikelets less than i cm. long. 



Lemmas keeled, l)i(lentate ; awn arising from alxjve the middle (sometimes wanting.) 



12. Triskitm ( p. 141 ) 



Lemmas convex; awn from below the middle. 



Hacbilla. prolonged behind the upi)er floret ; lemmas truncate and erose-dentate 



at summit; plants ijcrennial 15. .\ir\ (p. 1431 



Kacliilla not ]5rolonged ; lemmas tapering into 2 slender teeth; ])lants annual 



If)- Asi'Ris (p. 145) 



AGROSTIDEAE. 



Racbilla articulate below tiic glumes, these falling with the spikclet ; glumes awned; lemmas 

 awned from the tip. 



Spikelets pilo.se at base, in narrow loose simple [)anicles 20. GarnoTia (p. 155) 



Spikelets not pilose at base, in dense spikelike panicles 21. Polvpogon (p. 155) 



Racbilla articulate alx)ve the glumes. 



(ilumes not longer than the lemma. une(|ual ; sjiikelets awnless 23. Si'OROHoi.iis ( ]). 157) 



Glumes longer than the lemma, alv)Ut eciual. 



Glumes saccate at base; lennna long-awned ; inllorescence contracted, shining 



22. Gastridum ( p. 157 ) 



Glumes not saccate at base. 



Florets bearing at base a tuft of hairs iS. C.m.amaCrostis ( ]). 147 I 



Florets without hairs at base 19. .Vgrostis (p. 149J 



CHLORIDEAE. 



Spikelets with more than i perfect floret. 



Rachis not jjrolonged 24. Eleusine (p. 159) 



Rachis of spike extending iieyond the spikelets 25. D.\CTvi,oCTi:.\ifM (p. 161) 



[10] 



