The animal kingdom arranged after its organization. Forming a natural history of animals, and an introduction to comparative anatomy / By the late Baron Georges Cuvier, Tr. and adapted to the present state of science. The Mammalia, birds, and reptiles, by Edward Blyth, the fishes and Radiata, by Robert Mudie, the molluscous animals by George Johnston, M.D., the articulated animals, by J. O. Westwood, F.L.S.

  • Cuvier, Georges, baron, 1769-1832.
Date:
1849
Catalogue details

Licence: Public Domain Mark

Credit: The animal kingdom arranged after its organization. Forming a natural history of animals, and an introduction to comparative anatomy / By the late Baron Georges Cuvier, Tr. and adapted to the present state of science. The Mammalia, birds, and reptiles, by Edward Blyth, the fishes and Radiata, by Robert Mudie, the molluscous animals by George Johnston, M.D., the articulated animals, by J. O. Westwood, F.L.S. Source: Wellcome Collection.

    855/874
    soft tissues of the animal, no longer participates in its vital operations, and may he almost said to be dead; in fact the gelatinous flesh is frequently withdrawn from the lower part, so that it remains as an inert stony mass, whilst, the upper portion is actively growing. In some of the arborescent corals (Madrephyllidce), the stony matter appears to be entirely deposited in the substance of the polypes themselves ; which are seated only at the ex- tremities of the branches ; but in the more massive species (Madreporidce), it is deposited also in the connecting gelatinous flesh, and the polype-cells are scattered over the entire surface. The Order may be divided into the following families :— Section A. Body coriaceous or fleshy. Family 1. Actiniadce. Polypes separate and single. Family 2. Zoanthidce. Polypes gemmiparous, and associated by a common base. Section B. Body secreting a calcareous polypidom. Family 3. Madrephyllidce. Coral with terminal cells. Family 4. Madreporidce. Coral cellular throughout, the cells connected by a calcareous network, their own walls also being porous. All those massive corals, to which the formation of coral reefs and islands is chiefly due, belong to the second section of this order ; and most of them to the family Madreporidce. Whilst the animals of the first section are abundant in nearly all latitudes, those of the second are at present almost entirely restricted to tropical seas. The large amount of coral limestone , however, found interposed amongst various other stratified rocks, from the oldest even almost to the most recent, shows that they must have formerly had a much more extensive distribu- tion. Only one small 6pecies (Pocillopora interstineta) belonging to the third family, and three ( Turbivolia bo- realis, T. miUetiana, and CaryophyUia Smithii) belonging to the fourth, have been until recently known in British seas. At the last meeting of the British Association, however, Mr. Mac Andrew announced the very inter- esting discovery of a living Fungia dredged up off the coast of Zetland. Obdeb III.—ASTEROIDA. r'lG. 16.— Alcyonian Poj.vpr. This division receives its designation from the star-like appearance of the short thick tentacula, six or eight in number, when expanded around the mouth. These tentacula are unpro- vided with cilia; but a number of little projections may be seen along their margins, which probably increase their prehensile power. The mouth leads to a stomach, which is suspended in the midst of the general cavity of the body by partitions radiating from its walls ; the number of these partitions, and consequently that of the chambers surrounding the stomach, being the same with that of the tentacula. Instead of being closed at its lower extremity, however, like that of the Actiniform polypes, the Btomach of the Alcyonians opens into the canals that ramify through the fleshy mass in which they are imbedded; the orifice being surrounded by a circular muscle or sphincter, by the actions of which it may be ex- panded or entirely closed. The chambers which surround the stomach communicate above with the cavity of the tentacula, each of which has a small orifice at its extremity; whilst below they are continuous with the ramifying canals just mentioned; and the membranous septa which support the stomach do not cease at its lower extremity, but are prolonged downwards as plaits or folds of the lining of these canals, until they gradually disappear. Here, too, the life of the individual polypes is subordinate to that of the general mass ; and it is from the latter that all the extensions of the fabric by gemmation take place. On the other hand, the ova are developed in the substance of the membranous folds, and make their way outwards through the mouth. In this order we find a remarkable diversity in the charac- ter of the polypidom, together with a great general similarity in the structure of the polypes themselves. It contains no solitary species ; and the essential character, by which it is most distinguished from the Helianthoida, is the intimate connection of the individuals of the same mass. In the com- mon Alcyonium, the polypidom has something of a spongy texture ; being composed of a gelatinous flesh burrowed by a network of canals, and strengthened by a multitude of spiculeB of mineral matter, which form a sort of loose skeleton that extends throughout the mass, especially strengthening its surface. In the Tubipora musica, or organ-pipe coral, the external integument of each polype is completely consoli- dated into a calcareous tube. On the other hand, in the Red Coral, it is the centre which is thus hardened, forming a very dense stony axis, on the smooth surface of which not a vestige of polype-cells can be detected. This axis is clothed in the living state with a gelatinous flesh that is channelled out, like that of the Alcyonium, Fig. 17.—Alcyonium ; A, portion enlarged, showing the Polypes.