British ferns and their allies : comprising the ferns, club-mosses, pepperworts, & horsetails / by Thomas Moore.

  • Moore, Thomas, 1821-1887.
Date:
1881
Catalogue details

Licence: Public Domain Mark

Credit: British ferns and their allies : comprising the ferns, club-mosses, pepperworts, & horsetails / by Thomas Moore. Source: Wellcome Collection.

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    are mucli more durable^ and the plants, if in a mode- rately sheltered situation, become evergreen. These latter should be most extensively adopted for culture where ornamental effect is an object. The fronds of Ferns consist of two parts—the leafy portion; and the stalk, which latter is called the stipes. The continuation of the stalk, in the form of a rib extending through the leafy portion, and be- coming branched when the frond is divided, is called the racJds. If the frond is compound, that is, divided, so that there is another set of ribs besides the principal one, the latter is called the primary rachis, and the former the secondary rachis. In but few cases are our native species more highly compound than this. In practice, when the outline or division of the frond is mentioned, it is generally the leafy portion only that is referred to, exclusive of the stipes. The stipes is generally furnished more or less with membranous scales, which are sometimes few and con- fined to the base, and at other times continued along the rachis. Sometimes these scales, which are gene- rally brown, are large and so numerous that the parts on which they are situated acquire a shaggy appear- ance. The form of the scales, as well as their number and position and even colour, is found to be tolerably constant in the different species or varieties, and hence they sometimes afford marks of recognition. Whenever they are produced along the rachis, as well as on the stipes, they arc invariably largest at the base, and become gradually smaller upwards. In some species the leafy portion of the frond