42. 
Poa 
1. Plants not more than 25 cm. tall; annuals. 
2. Lemmas with webby pubescence at base, distinctly 
3-nerved, the intermediate nerves faint, thickly 
pubescent on the lateral nerves and keel; plants 
Paley SHES sinc cats cc clellotets leis cele se oisicle selcieis co ois eleieisie's io. Chapmamiana 
2. Lemmas glabrous at base, distinctly 5-nerved, 
somewhat pubescent on the lower half of all 
nerves, especially the keel; plants bright green... P. annua 
1. Plants more than 25 cm. tall; perennials. 
3. Creeping rhizomes present, 
4, Culms very flattened, 2-edged; lemmas glabrous 
or nearly SO) at bases ciel. wes alte ee ececwes cesses Es. Compressa 
4, Culms rounded or slightly flattened; lemmas 
with webby pubescence at base. 
5. Blades shorter than the culm; lower branches 
of (panicle in a whord) Of) 5. Secs ce sceivie oe vel epratensis 
5. Blades about equal to the culm in length; 
lower branches of panicle usually in 2's. 
Expected (P. cuspidata). 
3. Creeping rhizomes wanting. 
6. Lemmas glabrous at base, tips of lemma blunt 
ANd= SCATLOUS 0/001. wcle cv acc cleee ceive seviecseceves, Da nautumnalis 
6. Lemmas webbed at base. 
7. Lemmas slightly pubescent on the keel or 
glabrous on all nerves. Expected O26 trivialis). 
7. Lemmas pubescent on the keel and marginal 
nerves. 
8. Lower panicle branches spreading or reflexed 
at maturity; panicle erect, much longer 
than wide; intermediate nerves of lemma 
PLOMMAMEMtievensovereielofoveveKcte: sialic leveleieisie) elelesiols(eiereereni eS Vee citatals 
8. Lower panicle branches not reflexed at 
maturity; panicle long, open; intermediate 
nerves of lemma faint. Expected 
(P. palustris). 
