328 MR. L. LEWTON-BRAIN ON THE ANATOMY 
Royal Botanic Garden, Edinburgh. May 1901. 
Hairs rather more abundant above. Stereome rather more spread out under lower 
epidermis. Otherwise as above. 
(Pl. 36. fig. 4.) N. Wales. July 1900. 
Only three ribs and two groups of motor cells. Stereome forms an almost continuous 
layer under the lower epidermis, none on upperside. 
** Stereome in separate hypodermal strands. 
+ Stereome-strands not larger than principal vascular bundles. 
i Motor-cell groups small and restricted to a row on either side the midrib. 
§ Upper channel deeper and wider than the leaf is thick. Hairs few or none. 
AIRA PRECOX (Pl. 36. fig. 5). Burntisland, Fife. May 1901. 
Midrib slightly marked and two other very low ribs. Leaf rather thick and folded. 
No hairs. Bundles of first and third orders; all have double sheath. Stereome forms 
small bands below bundles, none above. 
AIRA CARYOPHYLLEA.  Elsing, Norfolk. June 1902. 
Midrib faintly marked, and one other rib on each side slightly marked above. Lower 
side angular. Lower epidermal cells with flat outer sides. Few sharp hairs above on 
ribs. Bundles seven, of second and third orders; both sheaths present, but inner is 
inconspicuous in smaller bundles. Stereome very scanty, small bands below bundles, 
none above. 
$$ Channel narrower than the thickness of the leaf, 
AIRA FLEXUOSA (Pl. 36. fig. 6). N. Wales. July 1900. 
Leaf-section angular.  Upperside reduced to a mere depression. Lower (outer) 
epidermal cells flat. Short hairs abundant on upperside. Five bundles, large central 
one of first order, others of second and third orders. All have prominent double sheath. 
Stereome forms almost a continuous band under lower epidermis and a band above 
midrib on upperside. 
ii Motor cells in all the (about 4) grooves. 
FrsrUCA OVINA. (See p.327, above.) (Pl.36.fig. 3.) 
FESTUCA RUBRA (Pl. 36. fig. 7). 
Upper leaf. Upperside with few ribs, midrib strongly marked. Hairs rather few and 
short above. Bands of stereome above and below most bundles, those below bundles 
stronger than those above. 
Tt Stereome-strands stronger than principal vascular bundles, and tending to fuse laterally. 
Rings of chlorophyll-tissue round the bundles. 
LEPTURUS FILIFORMIS (Pl. 36. fig. S. Newquay, Cornwall. J uly 1902. 
Leaf subulate. Upperside with few ridges and grooves. Hairs fairly numerous 
above, short and sharp; none below. Cells of lower epidermis flat, of upper rather 
