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The Scotch bonnet, scientific name ''Semicassis granulata'', is a medium-sized to large species of sea snail, a marine gastropod mollusk in the subfamily Cassinae, the helmet shells and bonnet shells. The common name "Scotch bonnet" alludes to the general outline and color of the shell, which vaguely resemble a tam o' shanter, a traditional Scottish bonnet or cap. The shell is egg-shaped and fairly large, in maximum dimension, with a regular pattern of yellow, orange or brown squarish spots. The surface sculpture of the shell is highly variable: the surface can be smooth and polished, have grooves, be granulated, or even be nodulose on the shoulder of the whorls. This species lives intertidally and subtidally on sandy substrates, and is found primarily in the tropical and subtropical Western Atlantic Ocean, from North Carolina to Uruguay. It is the most common species in this subfamily in North America. A similar-appearing sea snail in the Mediterranean Sea and Northern Atlantic Ocean, ''Semicassis granulata undulata'', is currently considered to be a subspecies. The exact taxonomy of this species has been unclear in the past: as well as the current combination ''Semicassis granulata'', 38 other combinations and synonyms exist. In the spring, the adult females of this species lay eggs in tower-shaped structures. The eggs hatch as veliger larvae, which can float in the plankton for up to 14 weeks before settling onto the seabed as tiny snails. Crabs are a predator of this sea snail. After the death of the snails, if the shells are still intact they are often used by hermit crabs. In 1965, in the US, the Scotch Bonnet shell was named as a state symbol of North Carolina, the first designation of a US state shell. ==Etymology== ;Scientific name The generic name is a combination of the Latin prefix ''semi'', meaning half, and noun ''cassis'', meaning helmet. The specific name of this taxon, ''granulata'', is derived from the Latin noun ''grana'' meaning grain. Here it is used in the diminutive form, meaning granulated, or covered in granules, i.e. small grains or pellets, referring to the shell sculpture. ;Common name The shell of this species was given the common name "Scotch bonnet" because of a vague resemblance to a tam o' shanter, a traditional tartan hat which used to be commonly worn in Scotland. The shell has a regular pattern of square or rectangular patches that are orange, tan, or brown in color. The shell can sometimes be smooth except for growth lines, but in other individuals it can have a sculpture of incised spiral grooves and even weak axial ribs which, together with the colored patches on the shell, create an effect that is reminiscent of the pattern of a Scottish plaid.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Scotch bonnet (sea snail)」の詳細全文を読む スポンサード リンク
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