382 STUDIES OF NATURE. 



the olives, fhaded like velvet of three or four co- 

 lours, the harp, embelliflied with the tints of the 

 moft beautiful tulips, the tunny, fpeckled hke the 

 partridge's wing, which walks along under the 

 fhade of the madrépores ; and all the families of 

 the univalves, which force their way into the fand 

 for Ihelter, the bivalves, as the ducal-cloak, fcar- 

 let-coloured and orange, and a multitude of other 

 migrating fhell-fiQi, are imprefled with colours 

 the moft lively, and form, with the different 

 grounds of the Sea, fecondary harmonies totally 

 unknown. 



But thofe which do not change their fituation, 

 as moft of the oyfters of the feas to the fouthward, 

 which frequently adhere to the rocks, or thofe 

 which are perpetually at anchor in ftraits, as mufcles 

 and the pinna-marina^ attached to pebbles by 

 threads, or thofe which reft on the bofom of the 

 madrépores, like veflels on the ftocks, as the 

 Noah's ark, or thofe which are entirely buried in 

 the heart of calcareous rocks, as the dail of the 

 Mediterranean, or fuch as are immoveable, from 

 their weight, which fometimes exceeds that of fe- 

 veral quintals, and pave the furface of flats, as the 

 thuilée of the Moluccas, and the large bivalves, 

 as the rocks, the burgos, &c. or thofe, in a word, 

 which, I believe, are blind, like our land-fnails, 

 fuch as lempits, which fallen therafelves, by the 



formation 



