CLASS GASTEROPODA: ORDER PROSOBRANCHIATA. 245 



GASTEROPODA. 



Mg. UW. 



SHELLS OP GASTEROPODS USED TOR ORNAMENTS.!. Cyndftum broderijnl; 2. Ce 

 rithlum; 3. Valuta imperialis ; 4. Cardium datum; 5. Phorus agglufmans; 

 6. Murex tenuispinus , 7. VermUus eburntus ; 8. Trochus niloficus ; 9. Lithodfanut 

 lithopkdgus; 10. Turritella. 



ORDER PROSOBRANCHIATA. 



General Characteristics. The Prosobranchs (gills 

 forward) have the gills placed in front of the heart. 



Muricidss (rock-shells). The Murex has the aperture of 

 its shell prolonged into a canal. * It is carnivorous, destroy- 



* The Shetlanders use this shell for a lamp, inserting the wick in the canal and 

 filling the hody of the shell with oil.-From these Mollusks the ancients obtained the 

 costly Syrian dye, the " purple " of Scripture. 



