Cliona, the boring sponge, destroys the shells and so injures the oyster; the boring annelid Leucodore also excavates the shell.
The sponge fisheries are of considerable importance.
The fishing and sponge industries are important.
The solid variety prepared by Staedel forms colourless, prismatic crystals which melt at -2° C.; it is decomposed with explosive violence by platinum sponge, and traces of manganese dioxide.
The sea fisheries are not important, with the exception of the sponge fishery, which is under the protection of the administration.
The (approximately pure) metallic sponge obtained is washed, made compact by compression, fused in a porcelain crucible in an atmosphere of hydrogen, and cast into sticks.
For sponge fishing no accurate statistics are available before 1896; in that year 75 tons of sponges were secured, but there has been considerable diminution since, only 31 tons being obtained in 1902.
Amphibrachium grows in the tissues of a sponge, Euplectella, and protrudes its hydranth into the canal-system of the sponge; and Lar grows on the tubes of the worm Sabella.
They derive this moisture from the air by means of aerial roots, developed from the stem and bearing an outer spongy structure, or velamen, consisting of empty cells kept open by spiral thickenings in the wall; this sponge-like tissue absorbs dew and rain and condenses the moisture of the air and passes it on to the internal tissues.
The waters of the Bahamas swarm with fish; the turtle procured here is particularly fine, and the sponge fishery is of importance.
Generally it is either dried, after being separated from the wash water, by means of common salt, upon a layer of which the moist nitroglycerin is gently run and allowed to drain or filter through, or it is filtered through a mass of dry sponge or similar dry and porous material.
The limestones contain Globigerina and other Foraminifera, the siliceous beds are made of Radiolaria, sponge spicules and diatoms, while the red clay closely resembles the red clay of the deepest parts of the oceans.
Sisal hemp is grown, sponges are found in some quantities off the coast and there are four sponge-curing factories on the Caicos Islands.
Among the commoner of the galls of the Cynipidae are the " oak-apple " or " oak-sponge " of Andricus terminalis, Fab.; the " currant " or " berry galls " of Spathegaster baccarum, L., above mentioned; and the " oak-spangles " of Neuroterus lenticularis, 9 Oliv., generally reputed to be fungoid growths, until the discovery of their true nature by Frederick Smith, 10 and the succulent " cherry-galls " of Dryophanta scutellaris, Oliv.
Then let us suppose that the inter-lamellar junctions already noted in Mytilus become very numerous, large and irregular; by them the two trellis-works of filaments would be united so as to leave only a sponge-like set of spaces between them.
Within the trabeculae of the sponge-work blood circulates, and between the trabeculae the water passes,.
The neighbouring coast is frequented by Greek and Italian sponge-fishers, the industry being a valuable one.
The scyphistoma of Nausithoe forms a branching network which grows in the sponge Esperella and forms the colonial polypoid organism named by Schulze Spongicola fistularis, by Allman Stephanoscyphus mirabilis.
They hold water like a sponge, but part with it under pressure to fissures by which they are intersected, and, in the case of the Upper Chalk, to ducts following beds of flints.
The sand-hills are not inherently infertile; the soil never bakes, is always receptive of moisture, absorbing water like a sponge and holding it well.
The oldest known Diatoms are represented by some specimens found entangled in the spicules of a Liassic sponge, and identified by Rothpletz as species of the recent genus Pyxidicula.
Most of the fishing boats, properly so called, start from the Adriatic coast, the coral boats from the western Mediterranean coast, and the sponge boats from the western Mediterranean and Sicilian coasts.
Soc. for 1903 and 1905) goes to show that during cloudy weather the summit of the mountain resembles an immense sponge, and that this condensation of moisture considerably influences the yield of the springs in the lower part of the mountain.
Batabano and Caibarien are centres of the sponge fisheries.
" Spongin," the matrix of bath-sponge, is insoluble in water and dilute acids, but soluble in concentrated mineral acids.
518, also " Organization of Sponge," Edin.
On passing a current of electricity, of which the volume and pressure are adjusted to the conditions of the electrolyte and electrodes, the anode slowly dissolves, leaving the insoluble impurities in the form of a sponge, if the proportion be considerable, but otherwise as a mud or slime which becomes detached from the anode surface and must be prevented from coming into contact with the cathode.
Jebel el-Akabah is much more barren than Jebel Akhdar, and the desert comes right down to the sea in Marmarica, whose few inhabitants are more concerned with salt-collecting and sponge fishing than with agriculture.
According to an account of the natives, a violent eruption of Kilauea occurred in 1789, or about that time, and deposits of volcanic sand, large stones, sponge-like scoria (pumice) and ashes for miles around are evidence of such an eruption.
There is also a sponge trade, but the former coral trade is depressed.
The people are chiefly employed in tobacco cultivation, silk and oil culture, poultry rearing and the sponge fishery.
A considerable sponge fishery is carried on round the coasts by traders from Smyrna.
Into rough 80-16 balls, each like a sponge of metallic iron particles with its pores filled with the still molten cinder.
Mushketov [1850-1902 ]) Cardium edule, Dreissena polymorpha, Neritina liturata, Adacna vitrea, Hydrobia stagnalis, in the Kara-kum desert, and Lithoglyphus caspius, Hydrobia stagnalis, Anodonta ponderosa and the sponge Metchnikovia tuberculata, in the Kizilkum desert.
The limestones of which they are mostly composed act like a sponge, absorbing the rain-water through their innumerable pores and fissures, and thus storing it up in the interior, afterwards to allow it to well forth in springs at various elevations lower down.
The sponge divers brought up sponges valued at £24,630.
The inhabitants take part in the coral and sponge fishing off the African and Sicilian coasts, and coral is worked in the town.
They are known as "Conchs," and engage in sponge fishing.
Either wrought, pig, iron sponge or iron bars are employed, and it is important to notice that the form in which the copper is precipitated, and also the time taken for the separation, largely depend upon the condition in which the iron is applied.
If much carbonaceous matter be present (and this is generally so when iron sponge is used as the precipitant) the crude product is heated to redness in the air; this burns out the carbon, and, at the same time, oxidizes a little of the copper, which must be subsequently reduced.
Grabbing the scrub sponge, she started cleaning the oven again.
Since 1885 great attention has been paid to the sponge fisheries of Tripoli, the annual value of which is about £30,000.
The sponge and oyster fisheries are also important.