Page:Aspects of nature in different lands and different climates; with scientific elucidations (IA b29329668 0002).pdf/82

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  • [Footnote: live would seem, however, to be very different in different

species, and especially in the more delicate ones which do not form such large masses.

Sir James Ross, in his Antarctic Expedition, brought up corals with the sounding lead from great depths, and entrusted them to Mr. Stokes and Professor Forbes for more thorough examination. On the west of Victoria Land, near Coulman Island, in S. lat. 72° 31´, at a depth of 270 fathoms, Retepora cellulosa, a species of Hornera, and Prymnoa Rossii, were found quite fresh and living. Prymnoa Rossii is very analogous to a species found on the coast of Norway. (See Ross, Voyage of Discovery in the Southern and Antarctic Regions, vol. i. pp. 334 and 337.) In a similar manner in the high northern regions the whalers have brought up Umbellaria greenlandica, living, from depths of 236 fathoms. (Ehrenberg, in the Abhandl. der Berl. Akad. aus dem J. 1832, S. 430.) We find similar relations of species and situation among sponges, which, indeed, are now considered to belong rather to plants than to zoophytes. On the coasts of Asia Minor the common sponge is found by those engaged in the fishery at depths varying from 5 to 30 fathoms; whereas a very small species of the same genus is not found at a less depth than 180 fathoms. (Forbes and Spratt, Travels in Lycia, 1847, Vol. ii. p. 124.) It is difficult to divine the reason which prevents Madrepores, Meandrina, Astræa, and the entire group of tropical Phyto-corals which raise large cellular calcareous structures, from living in strata of water at a considerable depth below the surface of the sea. The diminution of temperature in descending takes place but slowly;]*