ICHTHYOLOGY. 71 



species is divided by partitions, and is much more 

 beautiful than mother of pearl. 



Q. What renders the Murex remarkable ? 



A. It is that species of fish from which the Ty- 

 rians obtained their celebrated purple dye. The 

 inhabitants of Peru, on whose coasts it is found, 

 use it for the same purpose in the present day ; it 

 something resembles a large snail. 



Q. How many species of Bivalves are there ? 



A. Of Bivalves, or Fish with two shells, open 

 ing with a hinge, there are thirteen species ; Mya, 

 olen, Tellina, Cardium Maetra, Donax, Venus, 



iondylus, Chama, Area, Ostrea, Anomia, My. 

 tillus, Pinna. Of these, Solen, Ostrea, Mytillus, 

 and Pinna, are deserving attention. 



Q. What is the Solen? 



A. The solen, or Razor Sheath, has a long shell 

 resembling the handle of a razor ; it is found in 

 the sand by the sea side, where it buries itself in a 

 perpendicular direction, sometimes two feet deep; 

 the fishermen throw a little salt into its hole, when 

 the fish rises as if to see what is the matter, but if 

 not instantly caught, it darts down again, and can 

 never after be enticed to show itself. 



Q. What is the Ostrea ? 



A. Ostrea, or the Oyster, is too well known to 

 need description. Rock Oysters are sometimes 

 found the size of a common plate, and in the East 

 Indies there are oysters whose shells are two feet in 



