The next great group of sea-weeds to be noticed on the shore has many more kinds below low-water mark, where they are never uncovered, than above. They are the great dark, olive-colored, ribbon-shaped, wavy-edged weeds, which have a tough skin and roots, which adhere to rocks, and which are called tangles and laminariæ by botanists. Their proper position, as a rule, is not on the shore, for they almost characterize a particular zone of depth; but there are kinds to be met with on rocks and timber, close to the low-water mark, and on the shore. Some of them are very remarkable when they are placed, as they are in the north of England, on the sea-beaten parts of white or gray rocks. They then often form a dense layer--a sort of black, moving fringe, which is sometimes uncovered. Most of them flourish in the most boisterous seas, and it would appear that those which may, with some reason, be called shore-plants, because they are close to low-water mark, and now and then uncovered, are smaller and more delicate. Thus one kind, which has been called the weak, or the papery tangle (Laminaria fascia), has a stem not bigger than a bristle, which gradually widens into a frond about twelve inches long and two broad. It is greenish or brownish-olive in color, and is very fragile. It has the remarkable geographical distribution which is very common to all those weeds living on the brink of the sea, for it is found as far off as the Falkland Islands. On British coasts it covers sandy rocks and stones near low-water mark, and is to be found in the north of Ireland, the western islands of Scotland, and the southwest of England. Another kind fringes precipitous rocks at low-water mark, and is abundant on the shores of Scotland and of the north and west of Ireland, the west and southwest coasts of England, and the northeast coast. Mr. Harvey notices it as one of the kind luxuriating in a furious sea, although its frond can be readily torn with the hand. It has a stem as thick as a quill, and a root of many branching fibres. The frond, or ribbon-shaped leaf, is from three to twenty feet in length, and only grows three to eight inches broad. It has a midrib running down its whole length, and the following peculiarities: there are many little leaflets on either side of the stem before it merges into the broad frond, and the surface is perforated with small pores, out of which come tufts of shred-like fibres. It seems to be an everlasting weed, and the first growth in the frond occurs from the stem. The new parts are lighter colored than the old, and after a while intersection takes place, where the new part joins the old, and the old leaf falls. This plant, from the side leaves giving it a winged appearance, is called the Alaria (from _ala_, a wing), and it is eaten in some parts of Scotland and Ireland. The midrib is the delicacy, but it is very insipid. The Scottish name is badderlocks, or henware, and the Irish, murlins.