Paspalidium.] clvii. GRAMiNEiE (Stapf). 585 
Ch.ZUJL) 
2. P. desertorum^ Stapf. Perennial, tufted (often densely so) 
from a hard creeping or praemorse rhizome with extra vaginal innova- 
tions covered with glabrous smooth cataphylls. Culms usually 
ascending, sometimes trailing, and, if so, then generally not rooting 
from the more or less swollen nodes, but throwing up leafy branches 
and secondary culms, rather slender, terete, firm or hard although 
not quite solid, many- or (the secondary) few-noded, the internodes 
of the barren shoots sheathed all along, the upper of flowering culms 
more or less exserted. Leaves quite glabrous, very glaucous : sheaths 
terete or somewhat compressed and keeled, tight, very smooth, the 
lowest tough and often long-persistent ; ligules reduced to a ciliolate 
rim ; blades narrowly linear from an equally wide base, tapering to a 
fine point, from 1-9 in. by 1J-2J lin., flat or involute, or sometimes 
folded, subflaccid or slightly rigid, smooth, nerves numerous, fine, 
the primary lateral and the midrib slightly differentiated. In- 
florescences solitary, terminal, rarely with 1-3 additional ones from 
the uppermost nodes, erect, from 1 to over 6 in. long, of a varying 
number of appressed or subappressed spike-like racemes, distant 
below, approximate upwards, often gathered there together with the 
terminal raceme into a dense false spike ; common axis slender, 
subterete at the base, channelled adaxillarily, gradually becoming 
trigonous upwards, glabrous, smooth. Racemes sessile, straight, 
slender, 2-seriate, the lowest in tall specimens over 1 in. long, the 
following gradually, the uppermost rapidly decreasing in length, 
often only 3-2 lin. long ; rhachis very slender, rigid, triquetrous, 
wavy, 1 lin. wide, angles finely marginate, scaberulous, internodes 
less than J lin. long, pedicels extremely short, with subdiscoid tips, 
glabrous. Spikelets numerous, laterally contiguous, rarely sub- 
imbricate, ovate to ovate-oblong, acute to subacute, 1 J— 1^ lin. long, 
glaucous or more often tinged with purple, quite glabrous and smooth. 
Glumes very dissimilar ; lower broad-ovate* subacute or obtuse, 
more rarely rounded or truncate, up to f lin. long, membranous, 
3-nerved ; upper convex, almost as long as the spikelet and of the 
same outline, membranous, 5-nerved, nerves distinct, somewhat 
prominent upwards and anastomosing there. Lower floret : valve 
corresponding in length and shape to the spikelet, slightly depressed 
upwards, very similar to the upper glume in substance and venation ; 
valvule as long as the valve, keels marginate ; anthers f lin. long. 
Upper floret elliptic in outline, acute, almost as long as the lower : 
valve and valvule crustaceous, very delicately rugulose, shining, the 
former faintly 5-nerved. — Panicum desertorum, A. Rich. Tent. FI. 
Abyss, ii. 365 ; Steud. Syn. PI. Glum. i. 46 ; Schweinf. Beitr. FI. 
Aethiop. 300 ; Durand & Schinz, Consp. FI. Afr. v. 746. P. arabicum , 
Nees ex Steud. l.c. 63. P. geminatum , Schweinf. in Bull. Herb. 
Boiss. ii. App. ii. 19 (partly) ; Stapf in Kew Bulletin, 1907, 213. 
Nile Land. Nubia : Walled el Assal, Schweinfurth, 495 ! Wadi Mareg, 
Schweinfurth, 711 ! Wadi Yumga, Schweinfurth, 705 ! Cordofan : without 
