Photo by W. Saville-Kent, F.Z.S.] [Milford-on-Sea.
A YOUNG BRITTLE STAR-FISH (MUCH MAGNIFIED).
The arms of the brittle-stars are composed of loosely fitting, readily fractured joints.
The Sea-cucumbers—better known in the commercial world as Bêche-de-mer, or Trepang—represent the only group which possesses a substantial market-value. Its typical members present an elongate worm-like contour, but progress by means of extensile tube-feet, after the manner of the Urchins and Star-fishes, and have their dental, nervous, and muscular systems fashioned on the same five-sectioned basis. The mouth, which is situated at one extremity of the body, is surrounded by a series of ten or twenty delicately branched or mop-like tentacles, which can be protruded or retracted at the animal's will, and are used for seizing food. The skin of the typical sea-cucumber is more or less soft and flexible, and has embedded within its substance innumerable minute calcareous spinules.
The commercially valuable sea-cucumbers, or bêche-de-mer, are all inhabitants of tropical waters, the North-eastern Australian coast and the Malay seas yielding the most highly prized forms. The Queensland Great Barrier Reef, consisting of a series of coral-reefs extending for upwards of 1,000 miles at a little distance from the Australian mainland, represents one of the most productive areas for this marine delicacy, the bulk of which goes to the Chinese market. The fishery is prosecuted with the assistance mainly of the Queensland natives, who, either by diving or wading on the reefs at low tide, collect the creatures in vast quantities. On being brought to the curing-stations, the animals are emptied from the collecting-sacks into large caldrons, where they are allowed to stew in their own juice for about twenty minutes. Taken out of the caldrons, they are split open and eviscerated, dried for a short interval in the sun, and then placed in tiers on wire gratings in a smoke-house, where they remain for twenty-four hours. They should at this stage have shrunk up to about one quarter of their normally extended size, much resemble charred sausages in aspect, and should rattle like dry walnuts when bagged up for exportation. From £50 to £150 per ton are the prices that the better qualities of bêche-de-mer realise when well cured and delivered at Chinese ports. The chief culinary use to which the cured sea-cucumbers are applied is that of the concoction of soup, the best quality prepared taking rank with that made from swallows' nests. At the hotels and clubs in the leading Australian cities bêche-de-mer soup is held in high favour, and its more extensive introduction on the menu-cards of Western civilisation may be only a question of time.
Photo by W. Saville-Kent, F.Z.S.] [Milford-on-Sea.
A BRANCHING-ARMED BRITTLE-STAR.
The specimen is attached to a brilliant scarlet sponge.
Many species of sea-cucumbers inhabit British seas, but none possess that density of tissue which is essential for their economic conservation; the majority, moreover, are of comparatively small size, some few inches long only when fully extended, whereas the commercially valuable tropical ones may measure as much as from 2 to 3 feet. The mode of feeding of sea-cucumbers is somewhat interesting; the smaller species, with much-branching tentacles, generally affix themselves by their tube-feet to some object, and, extending their tentacles in all directions, utilise them, like those of a sea-anemone, for seizing any minute and suitable prey which may strike against them. The microscopic organisms on which they chiefly feed abound in the waters they inhabit, and one after the other, the branched tentacles having effected a capture, are gathered together and tucked bodily into the creature's central mouth and apparently half-way down its throat. The larger coral-frequenting species are provided mostly with mop-shaped tentacles. They crawl about leisurely in search of their food, mopping over the ground, and gathering up in their tentacles the minute shells and other organisms on which they subsist, which are collectively thrust with an indrawn tentacle into the throat. In some of the lower forms the tube-feet have disappeared, the integument is thin and semi-transparent, and the worm-like animal crawls about by means of its skin-spinules, which take the form of anchors or grappling-hooks. In an opposite direction they may develop a supplementary covering of dermal plates and a more rigid integument, which indicate their nearer relationship with sea-urchins.