THE MITRE SHELLS. 



193 



MUREX TEXUISPINA. 



beak. The lingual teeth of Murex seem well fitted for thus boring through the shells of other 



Molluscs on which all these sea snails are predatory.* The dye used in the manufacture of the 



celebrated " Tyrian purple" of the ancients was obtained from certain species of Murex. The 



small shells were bruised in. mortars, and the animals of the larger ones , 



were taken out. Heaps of broken shells of Murex trunculus and cauldron- 



shaped hollows in the rocks may still be seen on the Tyrian shore. (Wilde.) 



M. Boblaye noticed that on the coast of the Morea there is similar evidence 



of the employment of Murex brandaris for the same purpose. One 



hundred and eighty living species have been noticed ; they are of world- 



wide distribution. 



The Miiricicice not only possess the power of forming, but also of 



dissolving parts of their shells, and they use it in removing those external 



spines which, in the onward and continuous growth of the shell, would 



interfere with the comfort and convenience of the animal. 



Columbella is the name given to a genus of small but prettily-marked 



shells, living in shallow water, on sandy flats, or congregating on stones, 



having a long narrow aperture, a thick outer lip, dentated within, the 



inner lip being crenulated and the operculum very small. About 200 



species have been described, all being sub-tropical and widely distributed. 



The Columbella mercatoria of the West Indies was formerly used by the 



natives as " wampum " for barter or exchange. 



The genus Fasciolaria (from fasciola, a band) is an elegantly-formed 



shell, with round or angular whorls (like a Fusus in shape), having bands 



of colour running down its sides ; the inner lip has several oblique folds on it. The operculum is 



claw-shaped. Like the preceding genus, some species of Fasciolaria attain a very large size. The 



Fasciolaria gigantea of the South Seas attains a length of nearly two feet. 



The genus Mitra (the " Mitre-shell ") has an elevated spire, with an acute 

 apex ; the shell is thick, the aperture small, and notched in front, the columella being 

 obliquely plaited, and the operculum very small. The animal has a very long proboscis, 

 and when irritated it emits a purple liquid, having a nauseous odour. Its bright 

 colour-bands and ornamentation have led to the names of " Mitre-shell," " Bishop's 

 Mitre," " Tiara," &c. This is a very abundant form. Three hundred and fifty species 

 are known ranging from low water to a depth of eighty fathoms. They are mostly 

 denizens of the tropical seas. Many of them must be very abundant, and yet a 

 scientific person who only invests shillings in the purchase of shells may go on 

 for twenty years and find himself only in possession of a few species, and of one 

 common and brilliantly-coloured sort the Mitra episcopates. The most beautiful of 

 the Mitras is properly called regina, but the rarest is M. stainforthii, valued at 10, 

 of which Mrs. De Burgh possesses the original example. The same lady has the 

 only specimen in England of the equally valuable (but not equally beautiful) M. 

 zonata, which was brought up by the lead of a sounding-line from deep water off 

 Nice, and described by Marryat in the Linnean Transactions of 1817. 



The Turbinella (or " Top-shell ") is a very thick, solid shell, with a short spire 

 and a long canal. On the columella are several transverse folds. On the 

 coast of India, China, Siam, Tranquebar, and Ceylon the Shank-shell (Turbinella 

 pyrum} is carved by the natives, and placed in their temples. The reversed 



variety is held sacred by the Cinghalese, and from it the priests administer medicine to the 



sick. Another species is called the "Pap-boat" (Turbinella rapka). "It is used," says Sir J. 



Emerson Tennent, " on the Malabar coast (when scooped out internally and carved externally) 



to contain the sacred oil which is employed in anointing their priests." 



The " Spindle-shell," Fusus (called the " Keel Whelk " on the coasts of the Channel, and the 



" Buckie " in Scotland), is extensively dredged for the markets, being more esteemed in the north than 



* For a description of the lingual teeth, or " odontophore " of snails, see p. 222. 

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