67 



gynium usually shorter and scales commonly more obtuse. Sim- 

 ply a reduced form of C. anisostachys, 



C. tnbcrciilata. A clear species, with somewhat the port of 



narrow- spiked C. verrucosa ^ Muhl. 

 C. rhyncJiophysa : C. pliysorJiynca, Steud. Boeckclcr (Engler's 

 Bot. Jahr i. 364), refers this species to C nigro-inargin- 

 ata^ Schw. I can see no essential difference between the 

 plant and C ntgro-marghiata, but as this species has not 

 been found south of Carolina, the union may be delayed 

 until more material accumulates. 

 C. ttirhinata. (See No. 48). Much like C. cojninunis, Bailey, 

 from which it is distinguished, among other things, by the strongly 

 nerved pergynia. C. rigens Bailey, appears to be a distinct 

 species, and the following points of contrast between the two may 

 be made : C. turbtnata: Culms rather slender ; staminate spike 

 not prominent; bracts narrow, usually not much prolonged; 

 perigynium very short-beaked and entire ; scales hyallne-brown 

 on the margins, obtuse or muticous, not prominently nerved. 

 Schafifner's No. 222 from San Luis Potosi is this species (v. s. 

 Hb. Berol., where it is named C. Halleriajia by Boeckeler); C. 

 rigens: Culms stout and stiff; staminate spike large and prom- 

 inent; bracts, particularly the lowest, leaf-Hke and longer (3 to 

 4 in. long) ; perigynium larger, longer beaked, the beak sharply 

 cut Into short membranaceous white teeth ;. scales very acute or 



rough-awned with white-hyaline margins, green nerved on the 

 back. 



V, s. Hb. Orst. 



C. Orstcdii. Much like C. cladostachya^ Wahl., but the pani- 

 cle contains fewer spikes (3 tQ 4 spikes, or sometimes 

 more), which are longer and more erect ; perigynium 

 straight or nearly so, not divergent, less strongly nerved. 

 Plant stouter and more erect than C. cladostachya. Evi- 

 dently nearer C. polystachya^ Wahl. 



C, acrolepis. Looks much like a small and abnormal C. da- 

 dostachya. Spikes very few in the panicle, sometimes re- 

 duced to one and never more than three, staminate por- 

 tion very small or even wanting, ascending or erect; 

 perigynium erect and straight, the scales very sharp and 



