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The word snail is a common name that can be used for almost all members of the molluscan class Gastropoda which have coiled shells in the adult stage. However those snails which do not have a shell or only a very small shell are usually called slugs. And then there are snails which have a broadly conical shell which is not coiled, or appears not to be coiled, are often known as limpets.When the word snail is used in a general sense,Wholesale Jerseys, it includes sea snails, land snails and freshwater snails.The class of Gastropoda (the snails and slugs) is second only to the insects in terms of total number of species. Snails are extraordinarily diverse in habitat, form, behavior, and anatomy, and therefore what is true of one snail species may not at all be true of another.Snails can be found in a wide range of different and alike environments from ditches to deserts to the abyssal depths of the sea. The great majority of snail species are marine. Many others are terrestrial,Cheap Jerseys From China, and numerous kinds can be found in fresh water, and even brackish water. Many snails are herbivorous, though a few land species and many marine species are omnivores or predatory carnivores.Although the average person might perhaps be more familiar with terrestrial snails, land snails are in the minority. Marine snails have much greater diversity, and a greater biomass. Snails which respire using a lung belong to the group Pulmonata,Cheap NFL Jerseys China, while those with gills form a paraphyletic group, in other words, snails with gills are divided into a number of taxonomic groups that are not very closely related.Snails with lungs and with gills have diversified widely enough over geological time that a few species with gills can be found on land, numerous species with a lung can be found in freshwater, and a few species with a lung can be found in the sea.Although the word snail is often used for all shelled gastropods, the word snail can also be used in a much more limited sense, to mean various larger species of air-breathing (pulmonate) land snails. The majority of this article is about air-breathing land snails.Most snails move by gliding along on their muscular foot, which is lubricated with mucus. This motion is powered by succeeding waves of muscular contraction which move down the undersurface of the foot. This muscular action is clearly visible when a snail is crawling on the glass of a window or aquarium. Snails move at a proverbially low speed. They produce mucus in order to aid locomotion by reducing friction,Wholesale China Jerseys, and the mucus also helps reduce the snail’s risk of mechanical injury from sharp objects. This means that they can walk over sharp objects like razors without being injured.Snails also have a mantle, a specialised layer of tissue which covers all of the internal organs as they are grouped together in the visceral mass, and the mantle also extends outward in flaps, which reach to the edge of the shell and in some cases can cover the shell.When retracted into their shells, many snails with gills (including many marine, some freshwater and some terrestrial species) are able to protect themselves with a door-like anatomical structure called an operculum. The operculum of some sea snails has a pleasant scent when burned, so it is sometimes used as an ingredient in incense.Snails range greatly in size. The largest land snail is the Giant African Snail or Ghana Tiger Snail which can measure up to 30 cm. Pomacea maculata or Giant Apple Snail is the largest freshwater snail, with a diameter of up to 15 cm and a mass of over 600 g. The biggest of all snails is Syrinx aruanus, an Australian marine species which can grow up to 77.2 cm (30 inches) in length and 18 kg (40lbs) in weight.In the wild,Cheap Jerseys NFL, snails eat a variety of different foods. Terrestrial snails are herbivorous. Their diet can include leaves, stems, soft bark, fruits,Wholesale NFL Jerseys, vegetables and algae. Some species can cause damage to agricultural crops and garden plants, and are therefore often regarded as pests. Aquatic snails eat other varieties of food such as plankton, algae, plants, and other microscopic organisms that live underwater.A snail breaks up its food using the radula, which is a chitinous structure containing microscopic hooks called cuticulae. With this the snail scrapes at food, which is then transferred to the digestive tract. This is why, in a quiet setting, a large land snail can be heard crunching its food since the radula is tearing away at what it is eating.According to reports snails have been eaten for thousands of years. It should be noted though that wild-caught land snails that are undercooked can harbor a parasite,Cheap NFL Jerseys, Angiostrongylus cantonensis that may cause a rare kind of meningitis. (Source: Wikipedia Free Online Encyclopedia)
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