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XIII. Smooth-stalked Meadow-grass. 
Poa pratensis, L. 
, 
Explanation Fig. A. Entire grass in flower, shewing two stolons, a tuft of branches, and a panicle, 
of plate. , 1. The spikelet before flowering, shewing the two glumes and four lower pales. 
, 2. The same, shewing three pales detached and suspended by the web of woolly hairs (Dis- 
tinction from Poa annua). 
, 3. A lower pale seen from the side, shewing the hair along the marginal rib, along the 
keel, and at the base. 
, 4. The spikelet in flower, seen from the side, 
, >. The upper pale and the flower with the stamens removed. 
, 6, A group of false fruits (seeds), shewing the interlacing webs. 
, 7. The false fruit (seed) lying on its side, (Note. In figs. 7—12 the hairs have been 
removed). 
,, 9% The same from the ventral surface, shewing the stalk and inner pale. 
,, 9. Apical false fruit lying on its side; the stalk is half the length of the whole fruit, and 
is terminated by a globular rudiment. 
,, 10, False fruit (seed): — observe the truncate stalk, the upper pale without a groove and 
its keels overlapped by the lower pale. 
,, 441. False fruit, on its side, shewing the lower pale. (By a mistake on the part of the litho- 
grapher the ribs are too prominent.) 
,, 42. False fruit with the outer pale removed, lying on its side; shewing the ciliated keels 
of the upper pale. 
,, 43. Caryopsis, dorsal surface. 
,, 44. Caryopsis, ventral surface. 
, 15. Caryopsis, on its side, 
,, 46. Transverse section of the caryopsis: — the ventral surface (above) is slightly concave, 
and the back rounded. 
, 17. a—d. Transverse sections of a leaf-sheath at different heights, 
a. at the base; no fold, 
b. three-fourths above the base; the fold at a maximum. 
c. near the apex; the fold slight. 
d. an older sheath; the fold obliterated by stretching. 
,, 18. Transverse section of a leaf-blade, shewing the veins and »bulliform cells«. 
, 419. The short, obtuse ligule of a culm leaf. 
Botanical Botanical description. Smovoth-stalked meadow-grass forms tufts of branches loosely connected 
description. {ogether by long underground stolons. There are thus two kinds of branches (fig. A): — 4. the long, 
underground, horizontal stolons: extravaginal, 2. the aerial tufted branches: intravaginal, 
To form the stolon, the bud must first pierce the sheath which encloses it and thus become 
extravaginal, 
stolon lengthens it produces roots and colourless scale-leaves. The terminal scale-leaf forms a rigid cone 
covering the growing point and thus serves as a protecting and piercing organ, Ultimately the end 
bends up and becomes a leafy branch in the air (fig. A) which ullimately deyelopes a culm. The course 
of the stolon is not always horizontal; at times, especially when it comes from the centre of a large 
tuft, it descends vertically into the ground, but later on the end bends up as before to reach the light 
and air (fig. A). 
Growth is continued in a horizontal direction for a Jong distance underground. As the 
