342 



plants, particularly of Conferva chthonoplastes, the closely aggregated slimy 

 fibres of which form dense beds. Ed. P. J. 2. 392. The same circumstance 

 occurs in lakes and ditches : the bottoms of some of the former, in this 

 country, are no doubt increased by the curious production called Conf. 

 ssgagropila. To the peculiar distribution of Phaenogamous plants into certain 

 botanical regions, a fact familiar to all botanists, there is something analo- 

 gous in the submersed Flora of the ocean. We find latitude, depth, currents, 

 influencing the forms of Algae in nearly the same way as latitude, elevation, and 

 station, affect those plants which are more perfect; and as many of the latter 

 are confined to small extent of country, so do several of the Algae extend but to 

 short distances in the sea. Thus Oclonthalia dentata and Rhodomenia cris- 

 tata are confined to the northern parts of Great Britain, while many others 

 are peculiar to the southern parts ; and, on the contrary, many are cosmo- 

 polites of an unbounded range, such as Codium and Ulvacese, The latter 

 thrive best in the polar and temperate zones, Dictyotese increase as we approach 

 the equator, Fuci particularly flourish between the parallels of 55° and 44^*, 

 and, according to Lamouroux, rarely approach the equator nearer than 36°.. 

 The articulated or imperfectly formed fresh-water Alga3 are nearly confined 

 to the temperate and northern parts of the world, being almost unknown or 

 undescribed from within the tropics.. The number of species is scarcely 

 capable of being estimated. 



Properties. For what wise purpose the Creatorhas filled the sea and 

 the rivers with countless myriads of these plants, so that the Flora of the deep 

 waters is as extensive as that of dry land, we can only conjecture ; the uses to 

 which they are applied by man are, doubtless, of but secondary consideration; 

 and yet they are of no little importance in the manufactures and domestic 

 economy of the human race. Dr. Greville describes them thus {Algce Bri- 

 tanniccB,\\x.): — 



" Rhodomenia palmata, the dulse of the Scots, dillesk of the Irish, and 

 saccharine Fucus of the Icelanders, is consumed in considerable quantities 

 throughout the maritime countries of the north of Europe, and in the Grecian 

 Archipelago ; Iridsea edulis is still occasionally used, both in Scotland and 

 the south-west of England. Porphyra laciniata and vulgaris is stewed, and 

 brought to our tables as a luxury under the name of Laver ; and even the 

 Ulva latissima, or green Laver, is not slighted in the absence of the Por- 

 phyrse. Enteromorpha compressa, a common species on our shores, is 

 regarded, according to Gaudichaud, as an esculent by the Sandwich Is- 

 landers. Laurentia pinnatifida, distinguished for. its pungency, and the 

 young stalks and fronds of Laminaria digitata (the former called Pepper- 

 dulse, the latter Tangle), were often eaten in Scotland; and even now, though 

 rarely, the old cry, ' Buy dulse and tangle,' may be heard in the streets of 

 Edinburgh. When stripped of the thin part, the beautiful Alaria esculenta 

 forms a part of the simple fare of the poorer classes of Ireland, Scotland, Ice- 

 land, Denmark, and the Faroe Islands. 



" To go further from home, we find the large Laminaria potatorum of 

 Australia furnishing the aborigines with a proportion of their 'instruments, 

 vessels, and food.' On the authority of Bory de St. Vincent, the Durvillea 

 utilis and other Laminariefc constitute an equally important resource to the 

 poor on the west coast of South America. In Asia, several species of Geli- 

 dium are made use of to render more palatable the hot and biting condiments 

 of the East. Some undetermined species of this genus also furnish the ma- 

 terials of which the edible swallows' nests are composed. It is remarked by. 

 Lamouroux, that three species of swallow construct edible nests, two of which 

 build at a distance from the sea-coast, and use the sea-weed only as a cement 



