The Encyclopaedia Britannica; .. A dictionary of arts, sciences and general literature . may be three-lobed, five-lohed, seven-lohed,many-lohed, or trifid, quinqiiefid, septemfid, multifid, ac-cording to the number of the. divisions. The name pal-mate, or palmaiifid (fig. 101), is the general term appliedto leaves with radiating venation, in which there are severallobes united by a broad expansion of parenchyma, like theI palm of the hand, as in the Castor oil plant, Rheum palma-I tum, and Papaw. The divisions of leaves with radiating ven-ation may extend to near the base of the leaf, and the
The Encyclopaedia Britannica; .. A dictionary of arts, sciences and general literature . may be three-lobed, five-lohed, seven-lohed,many-lohed, or trifid, quinqiiefid, septemfid, multifid, ac-cording to the number of the. divisions. The name pal-mate, or palmaiifid (fig. 101), is the general term appliedto leaves with radiating venation, in which there are severallobes united by a broad expansion of parenchyma, like theI palm of the hand, as in the Castor oil plant, Rheum palma-I tum, and Papaw. The divisions of leaves with radiating ven-ation may extend to near the base of the leaf, and the namesbipartite, tripartite, quinquepartite (fig. 107), septemparti:e,digitipartite (Plate II. fig. 1), are given according as t^iepartitions are two, three, five, seven, or more. In Droseratlichotoma bipartite and tripartite leaves are seen. The termdissected is applied to leaves with radiating venation, having©umerous_narrow_ divisionsj as dissectun. When in a radiating leaf there are three primary partitions,and the two lateral lobes are again cloft, as in Uelleborus. Fig. 107. Fig. 108. Fia. 107.—Fire-partite leaf of Aconite. Such a leaf Is sometimes called palml-partito, palniately-pailite, or dissected. The venation is radiating, and thosegments of the leaf are cuneate, and each of them is cleft and toothed at thoapex Fia. 108.—Pednte leaf of Stinking Hellebore (Hdlehorui ftetidas). The venation Uradiating. It is a palmately-partite leaf, in which the lateral lobes are deeplydivided. When tho leaf hangs down It resembles the foot of a bii-d, and hencethe name. (fig. 108), the leaf is called pedate or pedatifld, from afancied resemblance to the claw of a bird. In all theinstances already alluded to the leaves have been consideredas flat expansions, in which the ribs or veins spread out onthe same plane with the stalk. In some cases, however,the veins spread at right angles to the stalk If they doso equally on aU sides, and are united by parenchyma, sothat
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectencyclo, bookyear1902
