PREFACE. Vll 



in, marked upon a shell ; the record of which is still 

 commemorated in the derivation of our terms, tes- 

 tament, and attestation. As one of the principal 

 agents of decomposition and gradual dissolution, 

 the geologist will find his researches assisted by an 

 examination into their rapid and astonishing powers 

 of perforating and disuniting rocks of calcareous 

 sandstone, limestone, marble, and even the hardest 

 masses of granite and porphyry, wherever they 

 come in contact with the ocean : and by a compa- 

 rative examination of the different stratifications of 

 marine testaceous depositions, he may eventually 

 be led to some important conclusions as to the 

 probable elevation of the general deluge. 



But the systematical conchologist has a loftier 

 and more noble object in his pursuit ; to unfold a 

 leaf from the great book of Nature : that portion 

 of which, respecting the treasures of our own 

 islands, it has been our study to contemplate, and 

 our wish to explain. Although we have not been 

 honored by the use of the library of the venerable 

 patriarch of natural history, Sir Joseph Banks, 

 without which, we are informed by a modern com- 

 piler on this subject*, " no writer can hope to at- 

 tain any tolerable degree of perfection ;" we have 

 not been entirely without the means by which this 

 study can be best understood and most faithfully 

 displayed. The whole of what is described, our- 

 selves have seen and accurately examined, with the 

 exception of such as are indistinct and not to be 

 found in cabinets, a few of the rarer and nearly 

 unique species, and some microscopic objects, the 



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b 2 number 



