XX11 EXPLANATION OF TERMS. 



Confluent. Running- into each other. 



Convolute. Rolling regularly over each other. 



Coriaceous. Of a tough leather like substance, 



Crenatf. Notched in a rather undulating manner. 



Croivn. The top of the shell. 



Cylindrical. Elongated and rounded, and of equal diameter 

 throughout. 



Decorticated. Worn down, as if by accident or design. 



Decussate. Furnished with fine lines both lengthways and 

 Across. 



f)enticles. Small tooth-like protuberances. 



Denticulate. Furnished with denticles. 



Dorsal. Appertaining to the outer-surface, or back part of 

 the shell. 



Duplicature. A fold tending backwards. 



Ears. Appendages on the sides of the hinge, as in most of 

 the Scallops. 



Effuse. Having the aperture emending from one end of the 

 shell to the other, and open at both extremities. 



Emarginate. Notched. 



Ferruginous. The color of rust or iron-mould. 



Flexuous. Running in a waved or indented manner. 



Fusiform. Shaped like a spindle; swollen in the middle, 

 and tapering to each end. 



Gape. '1 he opening in some of the bivalve shells, when the 

 valves are closed. 



Genus. A separate family, distinguished from all others by- 

 certain permanent marks, called generic characters, and to 

 which all such belong as are furnished with these characters ; 

 as the bivalves are known by the hinge and the teeth. 



Glabrous. Quite smooth, and without wrinkles, lines or 

 ridges. 



Granular, or Granulate. Covered with pimples or small 

 wart-like protuberances. 



Gutter. The elongated projection beyond the mouth in 

 some of the Murex tribe. 



Habitat. The natural local habitation of a shell, or the place 

 where it is generally found 



Hmge. The upper part of bivalve shells, where the teeth 

 find connecting cartilage are placed. 



Hyaline. Transparent like glass or water. 



Inflected. Bending inwards. 



Imbricate. Lying over one another, like the tiles of a house. 



Involute, Turning or rolling inwards. 



J/reguiar, 



