96 



POPULAR CONCHOLOGY. 



being placed in sea water, immediately recovered from 

 their inanimate state, apparently uninjured. 



The Cerithium giganteum is more than a foot in length, 

 and the only known specimen in existence is in the 

 cabinet of Lamarck*; it was fished up by an English 

 sailor in the neighbourhood of New Holland, and is, of 

 course, a recent shell. There are fossil specimens of this 

 species, even larger than the recent giganteum, found at 

 Grignon near Paris. 



The surface of these shells is rarely smooth, being gene- 

 rally covered with spines or prickles ; the regularity of 

 these projecting parts might furnish a sculptor with models 

 for innumerable designs in ornamental architecture. They 

 inhabit the sea ; but many live in salt marshes, or at the 

 mouths of rivers; they are occasionally found suspended 

 from the branches of trees by silken threads. 



Philippi mentions the following as sub-genera : — Pota- 

 mides Brongn. ; and Lampana Gray. 



Triforis. Deshayes. — Shell turret-shaped, sinistral, 

 composed of many whorls ; the aperture almost 

 circular, with a short, completely closed canal at 

 the base, another at the upper part, and occa- 

 sionally a third, which forms part of a varix. — 

 2 species ; also fossil. 



The recent species are found in the seas of 

 Australia, and also of Norway. This genus as 

 nearly resembles Cerithium. as Typhis does the 



Triforis 



JSlurex. 



Family 1 2. — PA L UDINA CEA. 



The animals have a short, truncated, and non-retractile 

 snout ; the tentacula arc long and slender, with the eyes 



* Now that of the Due do Rivoli. 



