INTRODUCTION TO BOTANY. ; lil 
22. A corm is a fleshy, starchy, and solid rootstock, shaped like a bulb, but not 
scaly, though often coated with the membranous leaf-bases of a previous season ; 
its buds are naked, and small in comparison to the fleshy base from which they 
spring. The Ixias, Gladioluses, &c., afford examples of this form of rootstock. 
_ § 4. The Stem. 
23. The Stem grows upwards from the root, bears buds which grow out into leafy 
branches, and finally produces flowers and fruit. i 
24. Stems are, : 
erect, when they spring perpendicularly from the root or stock ; 
dec , or ascending, when they spread nearly horizontally at the base, 
and then gradually turn upwards and become erect ; 
procumbent, when they spread along the ground the whole or the greater por- 
tion of their length ; 
prostrate, when they lie still closer to the ground ; 
creeping, when they emit roots at their joints. This term is also applied to 
rhizomes or roots, when they spread horizontally. 2 
tufted tae, when short, and growing in thick, cushion-like tufts or 
‘ 
diffues, when spreading loosely without being strictly decumbent or procum- 
bent 
25. Weak stems are said to twine when they support themselves by winding 
spirally round any object ; and to climb when they support themselves by their 
leaves, or by special clasping organs called tendrils, which are usually either imper- 
fectly formed leaf-stalks or flower-stalks. Twining stems are sometimes called 
voluble. 
26. Suckers are young plants formed at the end of creeping, underground root 
stocks. 
27. Scions, runners, and stolones or stoles, are names given to young plants formed 
at the end, or at the nodes (28) of branches or stocks, creeping wholly or partially 
above-ground, and sometimes to the creeping-stocks themselves. 
28. A node is a definite point on the stem or on a branch, at which one or more 
leaves are given off, and an internode is the portion of a stem comprised between 
two nodes. The nodes are pervious when the pith passes continuously through them, 
and closed or impervious when it is interrupted by partitions, as in grasses, &c. 
29. Leafbuds are small conical bodies, usually covered with scales, and found in — 
the ails (33) of leaves of the previous season or of earlier growth ; when occurring 
in other positions, as they sometimes do, they are considered adventitious or irregular. 
They contain the germs of future branches. ae, 
30. Branches (or leaves) are, es a i 
opposite, when two proceed from the same node at iy cages sides of the stem ; — 
whorled or verticillate, when pogo — same node, arranged 
regularly, like the spokes of a w round the stem. = g 
germinate, on pairs, when two proceed from the same node at the same side 
Of the stems 6c js et ee suas oe 
pobre 2 several spring from the same or nearly the same apparent 
rhe 
ape Oe aes 
” Glitrante, Wise one only proceeds from each node, one on one side, and the 
next above or below on the opposite side of the stem. 
decussate, when opposite, but each pair placed at right-angles to the one next 
above or below it ; 
distichous, when in two ranks ; tristichous, in three, Xe. 
scattered, when placed irregularly round the stem ; but this is often con- 
founded with alternate. 
_ seewnd, when all start from or turn towards one side of the stem, like the 
- teeth of a rake. 
- Branch 
es are, 
Sorked, when divide at the end into two or more equal branches ; 
_ dichotomous, eA each 2-pronged-fork is again divided, and this mode of 
_ division several times repeated ; ase : 
