On an arrow-poison from New Granada and on its botanical source / Joseph Tillie.

  • Tillie, Joseph.
Date:
1893
Catalogue details

Licence: Public Domain Mark

Credit: On an arrow-poison from New Granada and on its botanical source / Joseph Tillie. Source: Wellcome Collection.

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    amount of colouring-matter in the layer next the wood, which, however, is as broad as the other layers 1, 2, and 3 combined. The relatively narrow sclerenchymatous zone is also separated into two parts by an intermediate layer of cells resembling the inmost layer. The medullary canal is practically obliterated, and is excentric in position. The pale-grey coloured wood shows numerous small openings, and the large lacunae are scattered equally over the whole section. The tangential arrangement of medullary rays and openings is seen under the lens, and a few irregular strips of tissue, passing here and there circumferenti- ally, give a deceptive appearance of annual layers. The twig is cylindroid; thornless; slightly furrowed longi¬ tudinally; pale green; branches opposite; the bases of the branches relatively thick from the persistence of the attach¬ ments of the petioles, and the finest branches covered with short brownish downy hairs, just visible to the naked eye. The leaves are opposite and without stipules. The petioles are 2 mm. long, and the largest leaves, of which there are five, have an extreme length of 10*4 cm., and an extreme breadth of 4T cm.; the smallest is 3 cm. long and 1*6 cm. broad; and the intermediate sizes average 5 cm. long and 2‘8 cm. broad. The larger leaves are elliptical, with the base acute; the smaller sizes are ovate-elliptical; apices acuminate; margins perfectly entire and sparsely ciliated; membranous; upper surface light green, and under surface a paler green ; glabrous on both sur¬ faces, but veins on under surface are somewhat downy, espe¬ cially the midrib; veins prominent on the under surface, and of a reddish-brown colour; prominently 3- but also less distinctly 5-nerved; a strongly marked midrib gives of at its extreme base two very fine, but in the smaller leaves sometimes very distinct, wavy veins, which follow the margin of the leaf at a distance of about 1 mm., but become faintly marked near its apex; two strongly marked veins arise opposite or almost opposite each other about 2 mm. above the base, and follow the margin of the leaf at a distance of about 5 mm., and run into the apex at its margin. Secondary veins, which are fairly well marked on the under surface of the leaf, pass almost trans¬ versely from the primary veins and from a network. All the specimens, therefore, must be referred to the genus