86 BULLETIN 772, U. 8. DEPARTMENT OF AGRICULTURE. 
case with other grasses producing cleistogenes in the lower sheaths, 
the culms disarticulate at the lower nodes. Our species are of minor 
= SS 
TSS ES 
Wie. 42.—Pappophorum wrightii. Plant, X 4; spikelet, perfect floret, and cleistogene 
(below) from axil of lower leaf, all x 5. 
agricultural importance, the second and third sometimes constituting 
a fair proportion of the forage on sterile hills. 
