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fragments cemented together by a calcareous paste, the remit of the complete disintegration of many of them, and beneath this a nearly uniform calcareous paste, coloured grey by decomposed organic matter, and containing whole and fragmentary shells only sparsely scattered through it (pp. 206-7, vol. I.) Mr. Murray, one of the naturalists of the expedition, paid great attention to the question of the origin of this calcareous formation. Very early in the voyage he formed the opinion that all the organisms entering into its composition at the bottom are dead, and that all of them live abundantly at the surface and at intermediate depths over the globigerina-ooze area, the ooze being formed by the subsiding of theses shells to the bottom after death (p. 208, vol. I.) This, although not a new view, was a disputed one, Dr. Carpenter and Sir Wyville Thomson being formerly among these who thought that the evidence was exclusive that the foraminifera which formed the globigerina-ooze lived on the bottom. Sir Wyville (p. 210, vol. I) now acknowledges that he was mistaken, and he is of opinion that it may "be taken as proved that all the materials of such deposits (with the exception, of course, of the remains of animals, which we now know to live at the bottom at all depths, and which occur in the deposit as foreign bodies) are derived from the surface." "Mr. Murray finds the closest relation to exist between the surface fauna of any particular locality and the deposit which is taking place at the bottom."
The voyage has made known to us a number of new and beautiful forms of Sponges. One of these, Euplectella suberea, a beautiful and singular addition to these forms of European fauna, is figured at page 139, vol. I. It belongs to a very special group of sponges called the Hexactinellidæ, because the siliceous spicules throughout the family appear to be six-rayed. It is an old family abounding in many graceful shapes in the beds of chalk and grassland of the south of England, but until lately the fossil "ventriculites” were supposed to be extinct, and the discovery of their descendants living in the modern chalk beds of the Atlantic was one of the most interesting of the many corroborative evidences in favour of the view of the "continuity of the chalk."
The expedition has much enlarged our knowledge of deep sea fauna. It has introduced us not only to now sponge forms but to numbers of new crustaceans, corals, sea urchins, star fishes, bryozea, and fishes. The observations on the "Gulf-stream" and the fauna of the "gulf weed" (Soryassum baeriferum) are particularly interesting.
During such a protracted voyage opportunities for landing on shore were always gladly made use of, and some of the descriptions of what was seen on these occasions will, we have no doubt, be among the most attractive portions of the narrative to general readers. We may point out the description of the Bermudas Islands, and the formation and characteristic peculiarities of coral reefs as a good specimen of Mr. Wyville's descriptive powers. The geology of the Bermudas is sketched slightly, but with much precision. Some curious particulars are given of "Sand-glacier" at Elbow Bay, on the southern shore of the main island. The sand has entirely filled up a valley, and is steadily progressing inland in a mass five and twenty fact thick. It is covering up cottages, and has overwhelmed a cedar wood. The only way of stopping it artificially, says our author, is to cover it with vegetation. If planted in large numbers and tended and watered for a time it seems that oleanders and the native juniper will grow in the pure sand, and if they once take root the motion of the sand ceases. Some native plants, which form peculiar vegetation, sending out enormously long runners or roots—such as Ipomœa pescaprae and Coccolaba uvifera, and the crabgrass Agrostis véryiniea—then take hold of it and it becomes permanently fixed. The outer aspect of the sandhill of course slopes downwards towards the sea, and whenever