more rich in species than any of the other collections. The specimens were also the best preserved; for Professor Ehrenberg observes, that some[1] thus obtained, appeared as if still alive, though collected three years previous to his examination, and subjected to many vicissitudes of climate. The snow sometimes falls on the surface of the still ocean-water, and does not freeze, but floats a honey-like substance, often called Brash-ice: treated in the same way as the Pancake-ice it yielded an abundant harvest. 7. The mud and other soundings from the bottom of the ocean, when brought up on the arming of the deep sea-lead, or the chlam or dredge, generally contain the siliceous skeletons or coatings of many species, with the markings on their surface retained.[2] 8. The fresh and salt waters and muddy estuaries of the Falkland Islands, and similar localities, present us with species, occurring under circumstances, altogether similar to what accompany their allies in Europe.
The universal existence of such an invisible vegetation as that of the Antarctic Ocean, is a truly wonderful fact, and the more from its not being accompanied by plants of a high Order. During the years we spent there, I had been accustomed to regard the phenomena of life as differing totally from what obtains throughout all other latitudes; for everything living appeared to be of animal origin. The ocean swarmed with Mollusca, and particularly entomostracous Crustacea, small whales and porpoises: the sea abounded with penguins and seals, and the air with birds: the animal kingdom was ever present, the larger creatures preying on the smaller, and these again on smaller still: all seemed carnivorous. The herbivorous were not recognized, because feeding on a microscopic herbage, of whose true nature I had formed an erroneous impression. It is, therefore with no little satisfaction that I now class the Biatomacea with plants, probably maintaining in the South Polar Ocean that balance between the animal and vegetable kingdoms, which prevails over the surface of our globe. Nor is the sustenance and nutrition of the animal kingdom the only function these minute productions may perform: they may also be the purifiers of the vitiated atmosphere, and thus execute, in the Antarctic latitudes, the office of our trees and grass-turf in the temperate regions, and the broad leaves of the palm, &c, in the Tropics. Though we possess incontestible proofs of the abundance of silica, contained in the ocean, from its being secreted so copiously by these plants, we are ignorant of the process by which it is assimilated, and the chemical state in which it is suspended in the sea-water. The end these plants serve in the great scheme of nature is apparent, on inspecting the stomachs of many sea-animals, as above stated. Owing to the indestructible nature of their shields, they tell their own tale.
I shall now notice the most remarkable feature in the distribution of these organisms. They possess more than ordinary interest, many of the species being distributed from Pole to Pole; while these, or others, are preserved in a fossil state, in strata of great antiquity. There is probably no latitude between that of Spitzbergen and Victoria Laud, where some of the species of either country do not exist: Iceland, Britain, the Mediterranean Sea, North and South America, and the South Sea Islands, all possess Antarctic Diatomaceæ. The siliceous coats of species only known living in the waters of the South Polar Ocean, have, during past ages, contributed to the formation of rocks ; and thus they outlive several successive creations of organized beings. The Phonolite stones of the Rhine, and the Tripoli stone, contain species identical with what are now contributing to form a sedimentary deposit (and perhaps at some future period a bed of rock), extending in one continuous stratum for 400 measured miles. I allude to the shores of the Victoria Barrier; along whose coast the soundings examined were invariably charged with Diatomaceous remains, constituting a bank which stretches 200 miles north from the base of Victoria Barrier, while the average depth of water above it is 300 fathoms, or 1,800 feet.[3]
- ↑ Fragilaria pinnulata, and some Coscinodisci.
- ↑ The soundings were invariably in greenish mud, into which the lead sometimes sunk for two feet. At times, this mud seemed almost wholly composed of Diatomaceous remains.
- ↑ This great depth, reaching to within a quarter of a mile of the Barrier, whose height appeared nowhere to exceed 200 feet, proves that the latter does not rest on this bank. The accumulation, however, of snow on the
