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CULTIVATION AND AN ALTS IS OF PLANTS. 



Stalks. — The stalks are the offshoots from the stem, which directly support the leaves, 

 and are variously styled peduncles, pedicels, petioles, meaning respectively flowerstalks, 

 footstalks and leafstalks. 



Axil. — The axil is the angle formed on the upper surface, between the stem and leaf, 

 where the buds, called on that account axillary, spring from the stem (13). 



l:e^v'\^ss. 



'^.^ XDERS TOOD to lie expansions or elongations from the stem, 



leaves consist of a network of fibers or nerves in two distinct sets, 



1 one to each surface. The purposes they serve are mainly three: to 



expose a broader surface to the action of the light and heat, to aid 



' evaporation, and to facilitate the absorption of carbonic acid from the 



air. They discharge the function fulfilled by the lungs in the animal 



kingdom. They are called radical, when they spring around the root, 



the Dandelion; alternate, when only one appears on each joint of the 



stem, as in the Toad-flax (13); opposite, when in pairs opposite each other, as 



in \hc Mint (14); ■whorled, when in a circle around the stem, as in the Pin-ple 



Etipatorium'(i5); and tufted, when they appear in bunches or tufts at the top, 



as in the Ervngo (16), or as in the Palm. 



Leaves are further distinguished as sessile, when they sit, as it were, on the stem, 



without intervening stalks, as in the Eryngo (16); deciduous, if they fall annually, as in 



most trees and shrubs; and persistettt, if they survive the season, as in the evergreens. 



A leaf is simple, when composed of one piece only, as in the_ Round-leaved Bell- 

 flower (17); binate, ternate, quaternate or quinate, according as it has, on a common 

 stalk, respectively, two leaflets, as in the Listera; three, as in the Clover (18); four, as 

 in the exceptional four-leaved Clover; or five, as in the Ampelopsis {ig); pinnate, when a 

 number of leaves are arranged feather-like along the stalk, as in the Pea (20). A simple 

 leaf is sometimes wavy along the edge, as in the China Primrose (21), or has three lobes, 

 as in the Hypatica, five, as in the Castor-oil Plant, or seven, as in the Lady's Mantle (22). 

 Leaves are digitate, when they all spring, like so many fingers, from the tip of the 

 leafstalk, as in the ^'irginia Creeper (23); palmate, when the leaflets leave a space at their 

 common center, not unlike the palm of the hand, as in the Horse-chestnut (24); pcdotc, 

 or foot-like, as in the Chenopodiums, or when a palmate or other leaf has an additional 

 cleft in the edge, not as deep as the digitate, and hence called pedate, as in the Manthake 

 (25); peltate, or shield-like, when the stalk is attached at or near the center, as in the 

 Nasturtium (26); perfoliate, when the stalk passes through the leaf (27), as in the Bone- 

 set; connate, when two leaves are joined at their bases, the stalk passing through at the 

 junction, as in the Ljchnis (28). 



Again, by reason of peculiarities of the edges, leaves are called entire, when there is 

 an unbroken, gradual curvature of the margin, as in the Silene (29); crcnatc, crenellcd or 

 scollopped, when it is notched like a scollop slicll, as in the Ground Ivv (30); serrate, or 



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