30 POPULAR CONCHOLOGY. 



the shaft of a mine or tunnel." *— There is but 

 1 species. 



2. Siliquaria. Tube, irregularly twisted, 

 tapering towards one end, 

 which is sometimes spiral; the 

 other end open, and a longi- 

 tudinal fissure throughout its 

 whole length. Animal very 

 long and spiral, head distinct, 

 having two small tentacula, 

 with eyes at the base. — 7 spe- 

 cies, f 



Some naturalists consider 

 this animal to come under the 

 class Mollusca, and not Annulata. M. Au- 

 douin has examined the animal of one recently 

 found in India, and appears to be of the same 

 opinion. It is found also in the Mediterranean, 

 near Sicily. 



* Dr. Roget's Bridgewater Treatise. 



f So many additions are made almost daily to the 

 number of species of Mollusca, that those which are men- 

 tioned under each genus must only be taken as the num- 

 ber of well established species known at a certain period. 

 Almost all those which are mentioned in this work are 

 described by Lamarck and Deshayes in Les Animaux sans 

 Vertebres. 



