OUTLINES OF BOTANY. LXVII 
irregularly traversed by bhcbiooes cords or bundles of woody and vascular 
sri ssue, when # in con eae with the leaves. These vascular bundles 
ge aa ‘dir on as they pass down the stem Pegs in’ 
their Sai. “they, neladis only pre bast- or long wood- “belli, usually curv 
ing outwards towards the rind. The old tig becomes more compact 
and hacdoe ‘oipkists the ciroumaference than in the cent je The epidermis 
or rind either hardens s to prevent any increase of diameter in the 
stem, or it distanta “without increasing in thickness or F epliting or cast- 
ing off any outer lay 
200. In the Leaf, Ais structure of the Meee and principal ribs 
veins is the same as that of the young branches of which they are toed 
* fications. In She expanded portion of the le of the fibro-vascular system 
veins 
an 
cellular tissue. The majority of gto are horizontal, having a differently 
constructed upper and under surface. The cellular stratum formin 
upper surface consists of closely od cells, placed vertically, with their 
smallest ends next the surface, and with few or no stomates in the epi- 
dermis. In the stratum forming the suai surface, the cells are more 
table life, their stru cture, though still on the same plan, ray more single : 
their fibro-vascular a is less ramified, their cellular system more 
uniform, and there are few or no stomates. 
202. Bracts and Borst envelopes, when green age coisa ee 
resemble leaves in their anatomical structure, but in proport as they 
are reduced to scales or transformed into petals, they one chet gets 
and their systems, both meth dacs and cellular, become more s imple 
i and delicate. 
more e 
203. In the stamens and pistils the structure is still nearly the s 
The fibro-vascular system, surrounded by and dedhew ed with the twas 
tissue, is usually simple in the filaments and style, more or = ramifie 
in the flatt 
d ked, culiar form n- 
species, or often in large genera, or even Orders. The 
stigmatic GEESE of the pistil Es a mass of loosely cellular substance, 
‘agree net of epidermis, and usually is in communication with the ovary 
by aa nnel running down the centre of the style. 
204. “Th st on shy thickenings of the stem or ashi parts - the plants, 
succulent leaves 0 r branches, the fleshy, woody, or bony parts of fruits, 
the alb aie the thick fleshy parts of Seite 0s, Bak chiefly of 
largely developed cellular eat replete with starch or other menage 
Sek res apparently i ies cases for of eventu 
205. Hairs "at 1) are usually expansions or processes of the epidermis, 
and consist of one or more cells vo end to end. When thiek or har- 
dened into prickles, they still consist usually of ealbotae gern only, 
