576 GRAMINE^E. (GRASS FAMILY.) 



hand, differing from Panicum merely in the want of the lower glume ; which, 

 however, is occasionally present in some species, as a small scale. Glume and 

 empty palea few-nerved. Flower coriaceous, mostly orbicular or ovate, flat on 

 the inner side, convex on the outer. Stamens 3. (Said to have been a Greek 

 name for Millet.) 



* Spikes very numerous in a spiked raceme ; their thin and membranaceous or folia- 

 ceous rhachis broader than the spikdets, and keeled or boat-shaped. 



1. P. flUitans, Kunth. Glabrous; stems procumbent below and rooting 

 in the mud or floating; leaves lanceolate; rhachis (1" wide) projecting beyond 

 the small slightly pubescent spikelets into a tapering point, scabrous on the 

 back. (Ceresia fluitans, EU.) River-swamps, Virginia, S. Ohio, Illinois, 

 and southward. Oct. See Addeud. 



* * Spikes one or few ; the rhachis narrower than the spikelets. 

 *- Spikelets very obtuse, orbicular : spikes one terminal, and often 1-5 lateral. 



2. P. SCtaceum, Michx. Culm ascending or decumbent (1- 2 long), 

 slender; leaves (2" wide, flat) and sheaths clothed with soft spreading hairs; 

 spikes very slender (2' -4' long), smooth, mostly solitary on a long peduncle, and 

 usually one from the sheaths of each of the upper leaves on short peduncles or included ; 

 spikelets (" wide) narrowly 2-rowed. y. (Also P. debile and P. ciliatifolium, 

 Michx.) Sandy fields, Massachusetts, near the coast, to Illinois, and southward. 

 August. 



3. P. lUBVe, Michx. Culm upright, rather stout (l-3 high); the pretty 

 large and long leaves with the flattened sheaths smooth, or somewhat hairy ; 

 spikes 2-6, the lateral ones somewhat approximated near the summit of an elon- 

 gated naked peduncle, spreading (2' -4' long), smooth, except a bearded tuft at 

 their base; spikelets broadly 2-rowed (over 1" wide). 1J. 1 Moist soil, S. New 

 England to Kentucky, and southward. August. Either glabrous or sometimes 

 the lower sheaths, &c. very hairy. < ". 



- *- Spikdets acute: spikes always a pair at the summit of the naked peduncle. 



4. P. disticlllim, L. (JOINT-GRASS.) Nearly glabrous, rather glau- 

 cous ; culms ascending (about 1 high) from a long creeping base ; leaves linear- 

 lanceolate (2' -3' long) ; spikes short and closely-flowered (|'-2 / long), oneshort- 

 peduncled, the other sessile; rhachis flat on the back ; spikelets ovate, slightly pointed 

 (barely l" long). U (P. notatum, Fluegge, frc.) Wet fields, Virginia and 

 southward. July - Sept. 



5. P. Digitaria, Poir. Culms ascending (l-2 high) from a creeping 

 base; leaves lanceolate (3' -6' long, '- wide); spikes slender and rather 

 sparsely flowered (l'-4' long), conjugate, both sessile at the apex of the slender 

 peduncle; spikelets ovate-lanceolate (2'' long). (Milium paspalodes, EU.) Vir- 

 ginia (Pursh), and southward. 



59. PANICUM, L. PANIC-GRASS. 



Spikelets panicled, racemed, or sometimes spiked, not involucrate, 1^-2- 

 flowered. Glumes 2, but the lower one usually short or minute (rarely want- 

 ing), membranaceo-herbaceous ; the upper as long as the fertile flower. Lower 



