Soft-paste porcelain its soft-paste and hard-paste varieties is fraught with misconceptions", and various categories based on the analysis of the ingredients have been proposed instead. Some writers have proposed a "catch-all" category of "hybrid" porcelain, to include bone china and various "variant" bodies made at various times. At least in the past, some sources dealing with modern industrial chemistry and pottery production have made a completely different distinction between "hard porcelain" and "soft porcelain", by which all forms of pottery porcelain, including East Asian wares, are "soft porcelain". Chinese porcelain, which arrived in Europe before the 14th century, was much admired and
Porcelain crab are "Petrolisthes quadratus", found in large numbers under rocks in the intertidal, and the red-and-white polka-dotted "Porcellana sayana", which lives commensally within the shells inhabited by large hermit crabs. In Hong Kong, "Petrolisthes japonicus" is common. , some 4723 extant species porcelain crab had been described, divided among these 30 genera: The fossil record of porcelain crabs includes species of "Pachycheles", "Pisidia", "Polyonyx", "Porcellana", and a further 6 genera known only from fossils: The earliest porcelain crab fossil is "Jurellana" from the Tithonian of central Europe. Porcelain crab Porcelain crabs are decapod crustaceans in the widespread family Porcellanidae, which superficially