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XIX. Observations on Polypodium Oreopteris, accompanied with a Specimen from Scotland. By Mr. J. Dickson, Fellow of the Linnean Society.
Read January 5, 1790.
THIS plant has been mistaken by all our English botanists. By some it has been confounded with P. Thelypteris, by others with P. Filix mas; but it is very distinct from both. Doody, Dillenius, Ray, Hudson, Lightfoot, Bolton, &c. have all fallen into the same error. For a full account of this plant I beg leave to refer to Vogler, who has written an entire dissertation upon it, and calls it P. montanum. Wildenow gives it the same name. Ehrhart in his Plant. Crypt. Decas 3, No. 22, has published it by that of P. Oreopteris, which we prefer; as the name of P. montanum has been given to another species by Allioni. My opinion respecting this fern is supported by that of Sir Joseph Banks and Mr. Dryander, as well as of Dr. Smith and Mr. Jacquin; and, as the dissertation above alluded to may not be in every body's hands, I shall mention some of the most remarkable particulars in which this plant differs from P. Thelypteris.
1st. P. Thelypt. has a small creeping root, of which see a good figure in Schmeidel's Icones Plant, t. xi. P. Oreopteris has a large scaly root, wrapped and tied together with small strong fibres which cannot be separated without difficulty.
