Fig. 210: Fimbristylis annua: a, habit, X 1/2; b, spikelet, X 5; c, spikelet with lower 

 achenes fallen, X 5; d, scale, X 5; e, achene, X 5. (V. F.). 



with several prominent raised nerves, the often pale margin cartilaginous and 

 usually ciliate-scabrid; sheaths broad, smooth or pubescent, with a wide sub- 

 scarious margin that is smooth or pubescent, pale brown, toward its apex ciliate 

 and truncate or acute; ligule present as a horizontal line of short hairs; scapes 

 lax to rigid, ascending or erect, subterete basally, flattened or subterete above 

 at juncture with inflorescence; longest involucral bract similar to leaves in its 

 width and indument, shorter or longer than the inflorescence, the sheathing base 

 smooth or hirsute; spikelets lance-ovoid or oblong, 3-8 mm. long, acute, greenish 

 to tan or brown to a dark-reddish-brown, in a few- to many-spikeletted simple 

 or compound umbellate system of cymes (spikelets solitary in depauperate speci- 

 mens); fertile bracts broadly oblong to ovate, the apex acute to obtuse, the margin 

 entire, the surface smooth, the paler midrib seldom excurrent; anthers 1 or 

 rarely 2, about 1 mm. long; style 2-branched, flattened, ahe edges fimbriate from 

 the base to the branches or entire basally; achene lenticular, ovoid or obovoid 

 and quite tumid, about 1 mm. long, apiculate, white to brownish, often irides- 

 cent, striate-reticulate, the rectangular cells shallowly concave and horizontally 

 arranged in from 5 to 12 longitudinal rows per side, the longitudinal ribs more 

 conspicuous than the horizontal; surface of achene often verrucose, the warts 

 forming either along the longitudinal ribs or over entire cells. F. Baldwiniana 



410 



I 



