103 
Fig. 9. The lowest leaf of the bulbil (corresponding to the lower pale of the third flower); its 
sheath is laid open to shew the upper pale which is normal (behind it is a rudimentary 
flower ). 
10—414. Successive transitions between the normal lower pale and foliage leaf. 
, 10. The pale lengthening and beginning to bend inwards at the apex, anastomoses forming 
between the longitudinal veins, and reduction of the hairs. 
, 44. Apex more strongly curved, and the hair quite gone. At the base, a rootlet is beginning 
to develope. This figure represents the apical pale of a spikelet which is slightly viviparous. 
12. Sheath and blade are becoming differentiated. At @ to the left and at b to the right 
the ligule is beginning to be formed. 
13. A metamorphosed spikelet, the glumes removed. To the left, the lower pale of the second 
flower is distinctly metamorphosed into the sheath and blade of a foliage leaf, but the 
hair has not yet disappeared from the back. 
14. The pale represented in the previous figure, more highly magnified. 6. ventral view. 
¢. side-view. 
, 15. A lower pale aimost transformed into a foliage leaf, side-view. It bears an upper pale 
and a flower in its axil. 
16. The upper pale and flower removed from the axil of the preceding figure. 
, 17 and 18. The metamorphosed spikelet, side-view, natural size. 
, 19. A spikelet at the commencement of metamorphosis, the parts detached, side-view. 
20. Transverse section of a young leafy branch showing: two sheaths, the outer cut near the 
apex and split, the inner cut lower down and entire, and two folded leaf blades. 
,, 21. Transverse section of a leaf blade. 
,, 22. The ligule of a culm leaf and the split apex of its sheath. 
Botanical description. Alpine meadow-grass forms a simple, compact tuft of grass. All the 
branches are intravaginal and closely enveloped by the old persistent leaf-sheaths. Hence the compactness 
of the tuft and the bulbous appearance presented by the base of the plant (fig. A.) In this case, however, 
the bases of the leaves are not thickened as in an ordinary bulb. All the branches lie in one plane 
and the tuft is accordingly flat on the sides. Stolons are never produced. The culm bears very few 
leaves, it is smooth and from 12 to 18 inches in height. 
The leaf-sheath is entire for the greater part of its length (fig. 20). The sheaths of the radical 
leaves persist for a long time becoming, when old, dry membranes, enveloping the younger leaves and 
branches. The Jleaf-blade is short, but broad and sharply tapered off at the apex. The transverse 
section usually shews four or five principal veins (vascular bundles) on each side of the midrib; weaker 
veins lie between. Bundles of bast are found beneath the epidermis, both above and below the prin- 
cipal veins, but always ‘isolated from them (fig. 21). The /igule of the radical leaves is a mere margin; 
that of the culm leaves is longer and acute (fig. 22). 
The inflorescence is a panicle with many branches which are widely spread during flowering. The 
spikelets vary considerably. The common variety (Poa alpina, var. vulgaris, fig. A) has normal spikelets; 
each contains from four to six (fig. 1), rarely eight flowers; the pales are green, variegated with bronze, 
brown or violet tints. The glwmes are delicate membranes, three-ribbed, and slightly rough on the keel 
(fig. 4). The lower pale has five ribs (one dorsal, two lateral and two marginal), and certain parts 
are covered with long hair (fig. 2). The hairs occur along the dorsal rib and the lower part of the 
marginal ribs, but the lateral ribs have little or none. These hairs do not interlace and form webs 
like the »lana conjunctiva« so characteristic of the smooth-stalked and rough-stalked meadow-grasses 
(Poa pratensis and Poa trivialis). The hairs here are shorter, stiffer and have less tendency to curl 
than the »webs« of the Poas just mentioned. These structural differences correspond to a difference in 
function. In Poa pratensis, trivialis and some other species, the hairs on the pales serve to attach the 
false-fruits to passing animals. The rigid, spreading hairs of Poa alpina, on the other hand, increase 
Botanical 
description. 
