Algae Britannicae, Or Descriptions of the Marine and Other Inarticulated Plants of the British Islands, Belonging to the Order Algae; With Plates Illustrative of the Genera

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1830 edition. Excerpt: ...made it a species of Chordaria,-Lyngbye considered it a Furcellaria,Lamouroux a Gigartina: all equally remote from the truth. The peculiar characteristic is the spongy wart-like'fructification. When carefully examined with the aid of a microscope, the intemal structure of the frond is perceived to be cellular; but the cellules are elongated and arranged in such a manner as to have the appearance of filaments, especially in the centre, and towards the circumference. Many are constantly inclining in a curve towards the circumference, where they terminate, and constitute a dense coloured stratum'. During the developement of the fructification, these filaments are prolonged, become branched, and produce, here and there on the frond, spongy masses, within which are roundish clusters of wedge-shaped seeds, fixed by their base to a central 'point. My late correspondent, Captain Carmichael of Appin, who was remarkable rather as an indefatigable collector, than correct observer of plants, maintained that the spongy fructification of Polyides ought to be regarded as a distinct and parasitic Alga,---an opinion easily proved to be erroneous by microscopical examination, and which the very nature of the seeds might have convinced him was untenable. In sterile plants, globular white masses are freely deposited in the cellular tisue towards the circumference of the frond, and are easily broken down into minute spherical grains. They are very obvious when a thin transverse slice is placed in the microscope. The grains resemble those with which the cellules of the barren frond of Rhodomela suofusca are sometimes filled. M. Bory do St Vincent has described another species, brought from the coast of Chili, under the name of P. Durvillwi....