326 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
The name P. latifolium L. has been applied to this species by some authors but 
the type of the former belongs to a very different species.4 
DESCRIPTION, 
Plants perennial, decumbent at base, rooting and rather sparingly branching at 
the lower nodes; culms spreading or ascending, 0.5 to 1 meter long beyond the decum- 
bent base, rather robust, more or less angled, glabrous, rarely with a few appressed 
hairs below the glabrous nodes; sheaths densely short-ciliate, otherwise glabrous or 
papillose-hirsute toward the summit; ligule nearly obsolete; blades 4 to 15 cm. long, 
8 to 30 mm. wide, cordate-clasping, acuminate, glabrous or rarely with a few 
appressed hairs; panicles short-exserted, 10 to 25 cm. long, composed of a few ascend- 
ing or appressed, stiff, slender 
branches 3 to 10 cm. long, 
bearing throughout their length 
short, appressed branchlets with 
more or less secund spikelets, 
mostly two on each branchlet, 
one nearly sessile, the other on 
a pedicel about as long as the 
spikelet, the branchlets angled, 
scabrous; spikelets 5.5 to6 mm. 
long, 2 to 2.6 mm. wide, and as 
thick or thicker, obovoid, ab- 
ruptly short-pointed, glabrous; 
first glume about two-thirds 
the length of the spikelet, acute, 
3 to 5-nerved, second glume and 
sterile lemma equal, abruptly 
contracted into a short, keeled 
Fig. 367.—P. zizanivides. From specimen in Bonpland tip, 5-nerved, the lateral nerves 
Herbarium. of the lemma usually obsolete 
below the summit, the sterile 
palea about two-thirds as long as its lemma; fruit 4.7 to 5 mm. long, 1.8 to 2 mm. 
wide, becoming dark brown at maturity, smooth and shining, the lemma somewhat 
boat-shaped and with a short erose, laterally compressed crest at the apex, the apex 
of the palea similarly compressed and bent outward. 
Closely related to P. zizanioides is Panicum paucispicatum Morong > from Paraguay, 
which is distinguished from this by the smaller panicles, pubescent spikelets, and a 
more pronounced crest to the fertile lemma. 
DISTRIBUTION, 
Woods and copses, Mexico, West Indies, and south to Paraguay. 
Mexico: Ocuilopa, Nelson 3023; Trapiche de la Concepcion, Liebmann 394; San 
Juan Bautista, Rovirosa 624. 
GuatEeMALa: Dept. Alta Vera Paz, Tuerckheim 7699, 7700, 8785, 8796. 
Costa Rica: La Florida, Pittier 11276; Talamanca, Tonduz 8566; San Rafael, 
Pittier 2598. 
@ For a further discussion see Hitchcock, Contr. Nat. Herb. 12: 118. 1908. One of 
the sheets upon which Linneus has written the name “latifolium”’ is P. zizanioides, 
But this was received from Browne in Jamaica after the publication of the first edition 
of Linnzeus’s Species Plantarum and hence could not be the type of P. latifolium. 
b Ann. N. Y. Acad. Sci. 7: 262. 1893. 
