86 



BULLETIN 772, U. S. 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 



FIG. 42. Pappophorum wriglitii. Plant, X \ ; 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. 



