The ocean / By P.H. Gosse.

  • Gosse, Philip Henry, 1810-1888.
Date:
1846
Catalogue details

Licence: Public Domain Mark

Credit: The ocean / By P.H. Gosse. Source: Wellcome Collection.

    71/388 (page 53)
    nalis) is a native of the Mediterranean, but is much more familiar to us than our native species, of which there are many. The appearance which it presents is that of an irregularly-shaped mass, more or less rounded, composed of a brown woolly substance per- forated by innumerable pores in all directions, and having, in addition, wide canals communicating with each other, and terminating in round holes or mouths on the surface. But if we take a small por- tion of the substance, and place it under a common magnifying lens, we shall see that it is composed of shining, horny, nearly transparent fibres, which, by uniting with each other at all angles and distances, form a loose and very irregular network. Now, when in a living state, every fibre was inclosed in a coating of thin clear jelly, which formed the living animal, the horny fibres constituting, as I have inti- mated above, only the skeleton. Imbedded in the substance of many species, some British ones for example, are found sjoiculce, or needle-like crystals of pure flint, varying much in shape in various kinds, while other species have similar crystals of lime. Where these occur in considerable numbers, the Sponge does not possess elasticity; it may be crushed, but it will not regain its original form. It is a singular fact, that Sponges of these three different kinds are sometimes found growing close to each other, and all alike nourished by the same simple fluid, pure sea-water; yet they elaborate therefrom products so different as horn, flint, and lime. The animal nature of Sponges is not easily to be detected: no indication of sensation has ever