GRASS FAMILY. 39 



angular; spikelets in pairs at the ends of the long branchlets, oblong to oval- 

 acuminate, acutely pointed, one long- the other short-pedieeled, the latter over- 

 lapping and 1 to 1% times as long; lower bract 1-nerved, acute; upper 



5 to 7-nerved, pointed, about l'-j lines long; empty bractlet \ i \ lines long; 

 its palea obsolete; flower-enclosing bractlet obtuse, % line long. 



Said to occur throughout the State; lower Sacramento; Guerneville. A 

 v. iv variable grass. June-Oct. 



4. P. dichotomum L. Branched Panic. Perennial; stems 8 to 24 in. 

 high, at first erect and simple, then decumbent and branching from the pros- 

 trate nodes; sheaths with a tuft of soft hairs at the nodes, mostly softly-hairy; 

 lower blades nearly ovate, upper linear-lanceolate, smooth or hairy or velvety, 

 acute, l 1 ^ to 4 in. long, 2 to 3 lines wide; terminal panicle exserted, 1V. 2 to 

 3V 2 in. long, open, ovoid or pyramidal; those of the brandies short, often 

 barely exserted; panicle-branches filamentous; spikelets 1 line long, obovate 

 or ellipsoidal, obtuse or barely pointed, smooth or hairy; lower bract ' : ; as 

 long as the upper, roundish; upper 5 to 7-nerved. 



Common in moist sandy soils along the coast and in moist places in the 

 interior. Geysers; Pt. Eeyes. June-July. 



4. CHAETOCHLOA Scribn. Bristle-grass. 



Annuals. Leaf-blades flat. Panicle spikelike, dense, cylindrical, sometimes 

 interrupted below. Spikelets as in Panicum, but always awnless, the short 

 peduncles produced beyond them into one to several awn-like bristles which 

 are at one side of the spikelet, not forming a complete involucre. (Greek 

 chaite, bristle, and chloe, grass, referring to the tuft of long bristles at the 

 base of the spikelet. A genus easily recognized by the dense spike-like panicle, 

 usually bristling with numerous setae; these issue from the pedicels just 

 below the spikelets in the form of an involucre, and are not epidermal, like 

 true hairs, but appear to be abortive panicle-branches.) 



1. C. glauca (L.) Scribn. Bristly Foxtail. Stems erect, branching 

 below, 1 to 2 ft. high, leafy; mouth of the sheath clothed with long, silky 

 hairs; blades 4 to 12 in. long, 3 to 5 lines broad, scabrid or scabrous, sometimes 

 sparsely ciliate; panicles l 1 /^ to 2y 2 or 4 in. long, usually on a long, slender, 

 naked peduncle, though sometimes at first partially enclosed by the uppermost 

 sheath; bristles pale green or tawny yellow; spikelets oval, about 1 line long 

 and a little less broad, obtuse or sub-acute, pale green. — (Setaria glauca Beauv.) 



Introduced weed; occurring at Fresno. June-Oct. 



Tribe 3. Phalarideae. Canary-grass Tribe. 



Spikelets arranged in panicles, all alike, with 1 perfect flower which is 

 terminal, and 1 or 2 empty bractlets or staminate flowers below it. Empty 

 bractlets occasionally very small or rudimentary. Bractlet and palea of the 

 perfect flower alike, usually becoming indurated, laterally compressed, awn- 

 less, nerveless or with only 1 nerve. 



Perfect flower subtended by 1 or 2 empty bractlets which are often minute or rudi- 

 mentary. 

 Empty bractlets minute, entire, awnless or with minute bristles at the apex.. 5. PhalariS. 

 Empty bractlets equaling or exceeding the flower-enclosing bractlet, bifid and awned on 



the back (>. Antuoxanthum. 



Perfect flower subtended by 1 or 2 staminate flowers 7. HlEROCHLOE. 



5. PHALARIS L. Canary-grass. 

 Blades flat. Inflorescence a dense, spikelike, rarely interrupted, thyrse. 

 Spikelets crowded, 1 -flowered. Bracts about equal in length, boat-shaped, com- 



