21 P. interruptum. Culm strictly erect, wiry, tali (2 to3f); lvs. long, linear, 8 to 15' by 3 to 4", clothed with copious soft hairs, as well as the sheaths; spikes

3 or 4, raceme-like, 2 to 6' long, the spikelets ovate, acutish, in remote pairs distinctly pedicellate, rachis filiform. - Dry soils, La. and Tex. (Hale). (P. racemosum Nutt nec Jacq.) The inflorescence is almost paniculate.

16. MIL'LIUM, L. Millet Grass. (Probably from the Latin mille, a thousand, on account of its fertility.) Spikelets 1-flowered, not articulated with their pedicels; glumes 2, without involucre or awns; pales 2, shorter than the glumes, awnless, oblong, concave, persistent and cartilaginous, coating the caryopsis. (Comparing Millium with Panicum, it appears that the 2 glumes of the former are, in fact, a glume, and a pule of a second (abortive) flower, the upper pale and the lower glume being obsolete.) - Inflor. an open panicle.

M. effusum L. Culm upright, simple, smooth, 3 to 6 or 8f high; lvs. flat, 8 to 12' by 6" to 1', on smooth, striate sheaths; branches of the panicle clustered, spreading, remote; spikelets ovate, few and scattered, acute, about 1" long. - In woods, Penn. to Can. and Wis. Plant pale green. Summer.

17. AMPHICAR'PUM, Kunth. (Gr.Order CLVI Gramineae Grasses Part 9 2519 both or twain, Order CLVI Gramineae Grasses Part 9 2520 fruit.) Spikelets (apparently) 1-flowered and perfect as in Millium, but of 2 kinds, terminal, deciduous and sterile, the radical fertile; glumes 2, lanceolate, acute, awnless, as long as the 2 coriaceous pales; stamens 3: stigmas 2, plumous, purple. - Order CLVI Gramineae Grasses Part 9 2521 Caespitous, erect, strict, with erect, lance-linear lvs., the terminal fls. in a strict, contracted, slender panicle, the radical fls. are each solitary, on a slender ped., and subterranean.

A. Purshii Kunth. Pine barrens, N. Jer. (Long-a-coming. Jackson). Culm 2i high, glabrous. Lvs. 2 to 3' by 2 to 3", hairy, as well as the sheaths, the upper sheath long and without a leaf. Pan. on a long, exserted ped. Spikelets 1 1/2' long, the radical ones 2 1/2", veiny, the glume clasping the longer, neutral, single pale. Aug. (Millium Amphicarpon Ph.) i8. PAN'ICUM, L. Panic Grass. (Lat. pamicula, the mode of flowering, or pants, bread, which some species afford.) Glumes 2, unequal, awnless, the lower much smaller; flowers 2, dissimilar, the lower abortive or sterile, with 1 or 2 pales, the upper pale membranous; the upperOrder CLVI Gramineae Grasses Part 9 2522 . with the pales cartilaginous, polished, equal, concave, awnless, coating the caryopsis; stamens 3; stigmas plumous, purple. - Differs from Paspalum in the presence of the lower (true) glume. Panicles simple or compound.

§ Spikelets acute or pointed, very numerous, raccmed in large panicles. (*)

* Abortive flower neutral, consisting of a single palea. (a)

a Panicle capillary, with the spikelets solitary..............................................

No. 1, 2

a Panicle not capillary, dense-flowered.......................................................

No. 3

* Abortive flower neutral, consisting of 2 paleae (pales), (b)

b Panicle contracted, cylindric. Upper glume gibbous.............................

No. 4

b Panicle open.- Glume 3-veined. The 2 pales euqal...............................

No. 5

- Glume 5 to 7-veincd, - longer than abortive flower.........

No. 6, 7

- shorter than abortive flower........

No. 8

* Abortive flower staminate, with 2 pales. Tall, very smooth....................................

Nos. 9, 10

§ Spikelets obtuse or barely acute, solitary, pedicellate, not numerous. (**)

** Abortive flower (neutral) consisting of a single pale................................................

Nos. 11 - 13

** Abortive flower of 2 pales, the upper small and searious. (c)

c Leaves narrow, obscurely veined, 1 to 5" wide, (d)

d Spikelets densely fringed with silky hairs; fertile flower colored...................

No. 14

d Spikelets glabrous or sparsely pilous; fertile flower white, (dd)

dd Spikelets less than 1" long, roundish or oval: glume 5-veined...............

Nos. 15, 16

dd Spikelets 1 to 1 1/2" long, oval; glume 9-veined....................................

Nos. 17, 18

c Leaves broad, conspicuously veined, 5 to 20" wide. (e)

e A bortive flower usually staminate with 3 stamens.....................................

Nos. 18, 19

e Abortive flower neutral, never with stamens, (f)

f Plant very downy, with soft, dense, velvety hairs.................................

No. 20

f Plant smoothish or pilous-ciliate, branched

Nos. 21, 22

§ Spikelets barely acute, in short (1'), dense, secund, alternate spikes. Southern............

Nos. 23, 24

1 P. capillare. Culm nearly simple, assurgent and thick at base, 1 - 2f; lvs. hairy, broad-linear, acuminate, 4 - 6' long; sheaths covered with bristly hairs; pan. large, pyramidal, capillary, loose, expanding; spikelets small (2/3" long), often purple, oblong-ovate, purple, lanceolate, acuminate, smooth, on long, hispid peduncles; abortive fl. of 1 palea. -Order CLVI Gramineae Grasses Part 9 2523 Fields and roadsides, U. S. and Can. Aug. - Panicles often If or more long, with a very light, airy appearance. In poor or shady soils it is much reduced.

2 P. autumnale Bosc. Culm very slender, assurgent, 10 to 20' high; his. glabrous, lance-linear, at length convolute. 2 to 3' long: sheaths glabrous; pan. diffuse, bearded in (he axils, with long, strict, roughish, capillary, 1-flowered branches; spikelels oblong-lanceolate, acute, glabrous; glumes veiny, very unequal, the lower minute. - Sand hills, Mason Co., Ill. (Mead, in Gray's Manual),

3 P. proliferum Lam. Culm assurgent, geniculate at base, very smooth, thick and succulent; lvs. linear-lanceolate, 4 to 6'wide, 10 to 15' long, on tumid sheaths, ligules ciliate; pan large, pyramidal, terminal and axillary, smooth; spikelets oblong, acute, veiny, 1" long, densely racemed; lower glume 1/3 as long as the upper; abortive fl., with 1 pale. -Order CLVI Gramineae Grasses Part 9 2524 Marshes, especially brackish and sandy, Mass. to La., also along the Western rivers Aug., Septv (P. geniculatum Muhl.) In uplands more slender, not succulent.

4 P. gibbum Ell. Culm terete, assurgent, 2 to 3f, with black joints; lvs. lance-linear, glabrous, 4 to 8' by 4 to 8', on smooth, strongly striate sheaths; pan. densely contracted, often purple, fusiform, about 6' long, strict; spikelets near 2" long, obtusish, lower glume very small, upper very large, 11-veined, remarkably gibbous at base, upper pale nearly as long as the lower. -Order CLVI Gramineae Grasses Part 9 2525 Wet soils, S. States Jl. - Sept. (P. Elliottianum Schl.)

5 P. hlans Ell. Culm very slender, almost filiform, decumbent and rooting at the lower joints, about 2f high; lvs. narrowly linear, 8 to 16' long, glabrous; sheaths hairy only at the throat; panicle pyramidal, spikelets racemed, 1/2" long; lower glume half as long as the upper, neutral pales equal, conspicuous (gaping), a little longer than the fertile. - Damp pine barrens, S. States, common. Aug- - Oct. (P. debile Poir. P. divaricatum Mx.)

6 P. agrostoides Muhl. Culm compressed, glabrous, 1 1/2 - 3f high, often geniculate at base; lvs. long and numerous, cauline linear-lanceolate, carinate, rough-edged, on short, striate sheaths; panicles terminal and lateral, pyramidal, composed of racemed, spreading or deflexed branches; spikelets 1" long, purple, lance ovate, acute, crowded; upper glume 3-veined, 1/3. longer than the lower; upper neutral, pale, nearly as long as the lower. -Order CLVI Gramineae Grasses Part 9 2526 Meadows, frequent. July. (P. fusco-rabens Nutt.)

7 P. anceps Mx. Culm compressed, 2 to 3f; lvs. linear, carinate, very long, rough-edged; sheaths ancipital, pilous on the throat and margin; pan. erect, pyramidal, with subremote, subsimple, interruptedly racemous branches; spikelets 1 1/2" long, lanceolate, very acuminate, and when mature, forked; lower glume and upper pale half as long as the lower pale, scarcely shorter than the fertile flower; up per glume 7-veined - Wet soils, N, J. and S. States. Aug. - Nov.