266 SIR JOHN LUBBOCK ON 
AROIDES. 
Pistia Stratiotes, Linn.—Here also the bud is protected by a 
sheath which is free and inserted upon the axis opposite to the 
petiole; sheath membranous, transparent, and covering that 
portion of the bud not sheltered by the petiole, persistent. 
The axial bud is sheltered in the centre of the rosette by the 
surrounding leaves, and enclosed by the sheaths of both old and 
young, unexpanded ones. In their early stages the leaves are 
sessile, and more or less strongly involute at the margins. 
The axillary buds develop into stolons with a slender, terete, 
pubescent axis, bearing a rosette of leaves at the apex of an 
elongated internode. Before the stolon elongates these buds are 
sheltered by the older Jeaves of the plant. 
In Chamecladon ianceolatum, Miq. (fig. 132), the leaves are 
crowded on a short axis, alternate, arranged on the 3 plan, 
sheathing at the base, petiolate, lanceolate-elliptie, entire, cuspi- 
date, incurvinerved, glabrous, evergreen. The sheaths are largely 
developed, half the length of the petiole, dilated at the base, 
clasping the axis and several of the younger leaves. They are 
adnate to the petiole but free for a short distance at the apes, 
and resembling stipules in that respect, submembranous towards 
the margin only. 
The terminal bud is completely invested by the sheath of the 
youngest expanded leaf, and ultimately emerges from the free 
apical portion of the sheath, which is the first part to open. 
The axillary buds are protected by the investing sheaths of 
the older leaves, but only a few of them develop into shoots. 
This may be accounted for by the shortness of the stems ar 
internodes, and the consequent lack of space to expose additional 
sets of leaves to the light. 
Pothos (fig. 133).—The lamina is said to be absent in some 
species. The ‘Genera Plantarum’ describes the lower portion 
of the leaf as a winged petiole, but that of P. Loureiri, Hook. & 
Arn., seems to correspond with the sheath of many Orchidee, 
and which is also articulate with the lamina. 
The terminal bud is completely enclosed by the co 
sheath and lamina of several successive leaves, the lamina ; 
next younger leaf being the first to become protruded from t 
sheath of the most recently unfolded leaf. Every leaf 18 ° 
considerable size and age before it becomes exposed. 
nvolute 
of the 
