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THE

JOURNAL OF BOTANY

BRITISH AND FOREIGN.

Edited by

HENRY TRIMEN, M. B., F. L. S.

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WEST, NEWMAN & CO., 54, HATTON GARDEN.

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VII.

1878.

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Original Articles.

ON THE STRUCTURE OF THE PITCHER OF
CEPHALOTUS FOLLICULARIS.

By ALEXANDER DICKSON, M.D., Regius Professor of Botany in the University of Glasgow.

(TAB. 193.)

[Abstract of a paper read at the meeting of the British Association at
Plymouth, August, 1877.]

IN Cephalotus there are two forms of leaf:

1st. Non-ascidiform, with petiole and lamina of ordinary description; and

2nd. Ascidiform, with cylindrical petiole, from extremity of which depends a pitcher, with a lid attached by a broad base to that part of the orifice next the petiole and the main axis. The pitcher here appears to be a pouching from the under surface of the leaf, in this respect differing remarkably from those of Nepenthes and Sarracenia. It is scarcely safe, in absence of developmental evidence, to dogmatise on the subject; but, as matter of fact, the pitcher-lid in Nepenthes and Sarracenia springs from that portion of the orifice farthest from the axis; while in Cephalotus, as above stated, it springs from that portion next the axis. In Nepenthes, Sir J. D. Hooker has shown that the leaf-apex is represented by a bristle-like process at the back of the hinge of the lid (Fig. 2, ap). In Sarracenia the lid itself would appear to be the terminal lobe of the leaf. In Cephalotus, also, it seems scarcely possible to doubt that the lid represents the terminal lobe of the leaf, and, if so, the pouching, as already said, must be from the lower leaf-surface. The Cephalotus pitcher exhibits on its outer surface three well-marked wing-like processes, one median (Fig. 1, mdw) placed dorsally (away from the axis), and two lateral directed obliquely. The lid (Fig. 1, 1) of the pitcher is somewhat concave towards its inner surface, and exhibits strongly-marked ribs branching dichotomously, and connected by transverse smaller veins. It is usually more or less streaked with red, and towards the margin are to be seen, in the areola between the veins, translucent spots where the parenchyma is deficient, and which remind one of those on the upper part of the pitcher of Darlingtonia. From the outer surface of the lid, from the winglike ridges, and also from the margins and petioles of the nonascidiform leaves, more or less elongated pale brown hairs spring of very remarkable structure. The orifice of the pitcher is furnished with a cartilaginous corrugated rim produced internally into a

N. S. VOL. 7. [JANUARY, 1878.]

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