26 Phalarideae 



7. CENCHRUS L. Bur-grass. 



Annua] or perennial grasses with usually flat leaves 

 ami spike-like inflorescence. Spikelets subtended by a 

 spiny involucre, which is deciduous at maturity with them. 

 Glumes 4, the first hyaline, the second and third mem- 

 branous, the latter sometimes subtending a palea and 

 staminate flower, the fourth chartaceous, subtending a 

 palea of similar texture which incloses a perfect flower. 

 Stamens 3. Grain free, enclosed in the glume. 



1. C. tribuloides L. Culms erect or decumbent from an an- 

 nual root, usually robust, 15—45 cm. high, freely branching; 

 sheaths generally very loose, compressed smooth ; leaves 6-10 

 cm. long, 4-8 mm. wide; spikes 25-50 mm. long; involucres 

 crowded on the scabrous rachis, globose, pubescent except at the 

 base, spines stout; spikelets 2-flowered, about 6 mm. long. 



Occasional in orchards and gardens. San Bernardino, Parish; Rialto. 

 Native of Europe. 



Tribe 3. PHALARIDEAE. Canary-grass Tribe. 



Spikelets more or less laterally compressed, 1-flowered 

 or rarely 3-flowered ; glumes 5, the first 2 empty and 

 below the articulation of the rachilla, the third and 

 fourth above the articulation, usually empty or rarely 

 subtending staminate flowers, very unlike the other ones, 

 sometimes reduced to bristles, the fifth glume with a 

 1 -nerved or nerveless palea and a hermaphrodite (lower. 

 Represented with us by the single genus. 8. Phai.akis. 



S. PHALARIS L. Canary-grass. 

 Annual or perennial grasses with Hat leaves and 



Bpike-like, capitate or narrowly paniculate inflorescence. 

 Spikelets crowded, l-flowered. Glumes 5, the first and 

 second aboul equal in Length, strongly compressed later- 

 ally, usually wing-keeled, the third and fourth much 



