OSTBEAD*. OYSTER. 83 



los Rel. Descalzos de S. Francisco,' etc., 1738, mentions 

 the use of great oyster-shells for "holy water," and 

 speaks of one known to be ninety years old, by the 

 layers of its shell. But I fancy he must mean the shell 

 of the Tridachna gigas, as we know it is used for that 

 purpose ; and in the church of St. Sulpice in Paris are 

 two of these shells resting upon rock-work in marble, 

 by Pigalle ; they were given to Francis I. by the Re- 

 public of Venice. In the ' Intellectual Observer,' vol. i. 

 p. 483, is an account of an "oyster-shell" island by M. 

 Aucapitaine, on the east coast of Corsica, composed of 

 layers of shells, bearing some resembla,nce to the shell- 

 mounds of St. Michel-en-1'Herm, in La Vendee. This 

 island is formed of still-living species, and is between 

 three hundred and four hundred yards in circumference, 

 the greatest elevation about thirty yards, and the mean 

 elevation rather more than two yards above the level 

 of the sea. The Romans are said by the fishermen to 

 have deposited the shells of the oysters there, which 

 they salted for exportation, but M. Aucapitaine does 

 not believe in the artificial origin of this island. 



According to M. de Quatrefages, the shell-mounds of 

 St. Michel-en-1'Herm are composed of oyster, mussel, 

 and scallop shells, of the same species as those living 

 now in the neighbouring seas. Many of them have 

 their valves still connected by the ligament which forms 

 the hinge, and they have not even changed colour. 

 The three banks of St. Michel-en-1'Herm are about 

 seven hundred and thirty yards in length, three hundred 

 in width, and rise about ten to fifteen yards above the 

 level of the surrounding marshes. 



Mr. Buckland mentions a large heap of oyster-shells 

 in Galway Bay, at a place called Creggauns; another 



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