Aira.] GRAMiNEJii. 689 



E.Med. — In a ditch in Appulduroombe park. In sevel'al marsh-uieadow 

 ditches in Sandown level, above Alverston mill, one of which I found nearly filled 

 with it. Under the cliff at Foreland, Dr. BelL-Salter. Pond near the village of 

 Pan, Mr. Snooke. 



Whole herb quite smooth, very brittle and tender. Culms procumbent or float- 

 ing, 2 — 3 feet long, branched, rooting at the white swollen lower joints with bun- 

 dles of whitish fibres, their flowering extremities erect. Leaves short, linear, 

 bluntish, often bifid at the point, quite flat above, with a sharp narrow keel be- 

 neath, pale green, glabrous, with long, loose and smooth sheaths. Ligule short, 

 broad, pointed, mostly torn. Panicte erect, of many distant sets of half-whorled, 

 unequal, spreading, angular, compound branches, that are sometimes deflexed. 

 Florets i — 4, greatly longer than the glumes, the upper one shortly pedicellate. 

 Glumes green or purple, much shorter than the florets, [very unequal, truncate, 

 eroso-dentate ; outer one much the smaller and shorter, nerveless; inner one 

 3-ribbed at the base only. Palece equal, bluntish, membranous, erose at their 

 summits, outer one with 3, inner with 2, very strong prominent ribs ; this last is 

 hollow like the outer valve, and encloses the stamens, &c., contrary to the usual 

 structure in grasses, in which the inner palea is flattened and empty, the outer 

 only embracing the organs of reproduction. Anthers pale yellow. Styles but lit- 

 tle branched or feathery, approximate. 



XII. AiEA, Linn. Hair-grass. 



" Panicle lax (rarely contracted). Spikelets laterally com- 

 pressed, with 2 (or rarely 3 or 1) perfect florets and sometimes a 

 neuter one which is usually rudimentary. Glumes 2, unequal, 

 about as long as the florets, the outer 1 -nerved. Glumellas mem- 

 branaceous and thin, hairy at the base ; the outer one awned at 

 the back, with or without faint lateral nerves, toothed or entire or 

 bifid but not setigerous at the end. Caryopsis glabrous." — 

 Br. Fl. 



* Panicle close or subspicate. 



1. A. prcRCOX, L. Early Hair-grass. "Panicle contracted 

 oblong, spikelets somewhat acute at the base, florets scarcely vil- 

 lous at the base about as long as the glumes, awn twisted inserted 

 below the middle and usually near the base longer than the 

 glumes, leaves setaceous." — Br. FL p. 529. E. B. t. 1296. 

 Host. Gram. Aust. iv. 22, t. 37. Parn. Gr. t. 24. 



On dry sandy or gravelly heaths, pastures, wall-tops and waste ground; not 

 unfrequent. i^/. May, June. Q. 



E. il/erf.— Plentiful a few years back on the Dover, just behind the saw-pit, but 

 I believe now destroyed by the deposition of broken brick and other rubbish. 

 Near the top of the hill at Apse castle, abundant. On Boyal heath. [On 

 St. Helens spit, plentifully, A. 6. More, Esq., Edrs.] 



A small grass, for the most part forming caespitose often depressed tufts. Root 

 annual, of several slender hair-like fibres. Culms several, erect, often spreading 

 nearly flat or radiating, from an inch or 2 inches to a span long, slender, rigid, 

 shining and glabrous, leafy nearly or quite to the summit, angular above and 

 striated, tumid at the joints, and at the lower ones often geniculate, in dry sea- 

 sons and situations often reddish. Leaves mostly if not wholly confined to the 

 stem, very short, linear, suberect, from the involution of their margms appeanng 

 setaceous, obtuse, rough-edged, the inferior ones soon withering. Sheaths slightly 

 tumid, ribbed and angular, smooth, the uppermost much longer than their leaves, 

 -the rest shorter or about equal to the latter. Ligule large, lanceolate or oblong. 



