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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1895 Excerpt:...base give off branches that supply the thick stipules within which they branch and anastomose to form a network. These bundles in Angiopteris are arranged in several circles, or according to De Vriese and Harting,3 the central ones form a spiral. In the rachis of the last divisions of the leaves, however, both of 1 Bower (2), p. 579. 2 Holle (2), p. 217. De Vriese (1). Marattia and Angiopteris, there is but a single axi il bundle, as in the petiole of the cotyledon. Fig. 142, B shows a cross-section of a pinnule from a large leaf of A. evecta, which has much the same structure as that of Marattia. The central vascular bundle is horse-shoe shaped in section, and shows a central mass of large tracheids with reticulate or scalariform markings, surrounded by the phloem made up of very large sieve-tubes much like those of Botrychium, and with these are the ordinary protophloem cells and bast parenchyma. A distinct bundle-sheath is absent, as, according to Holle,1 it is from all the bundles in both Marattia and Angiopteris, except those of the larger roots. The bulk of the ground tissue is composed of large parenchyma cells, but on both sides just below the epidermis is a band of colourless cells which resemble exactly the collenchyma of Phanerogams. In the base of the petiole this becomes harder and forms a colourless sclerenchyma, according to Holle,2 which in Dancea is replaced by brown sclerenchyma like that of the true Ferns. In the lamina of the leaf in Angiopteris too, the arrangement of the tissues is strikingly like that of the typical Angiosperms. A highly-developed palisade parenchyma occupies the upper part of the leaf beneath the epidermis, which bears stomata only on the lower side of the leaf. The rest of the mesophyll is composed of the spongy gre...