172 



by which the valves are united, 

 situated uear the beak. 



Cauda, the elongated base of the ven- 

 ter, lip, and columella. 



Cicatrix, the glossy impression in the 

 inside of the valves, to which the 

 muscles of the animal are affixed. 



Ciliate, edged with parallel hairs, 

 bristles or appendages, like the eye- 

 lids. 



Cinereous, of ash colour, of the colour 

 of wood ashes. 



Clavate, club-shaped, thicker towards 

 the top, elongated towards the base. 



Cochleae, shells of one piece, uni- 

 valves. 



Cochleate, twisted like a screw or the 

 shell of a snail. 



Columella, the upright pillar in the 

 centre of most of the univalve 

 shells. 



Commissure, a joint or seam. 



Complicated, doubled together. 



Compressed, perpendicuWly squeezed 

 together, in opposition to depressed, 

 '.vhich is horizontally flattened. 



Concamerated, arched over, vaulted. 



Concamerations, divided into compart- 

 ments, as in tlie Nautili. 



Concave, hollowed out like a bowl. 



Concentric, running to a centre. 



Conchae, shells consisting of two or 

 more pieces or valves, bivalves, or 

 multivalves. 



Cone, the form of a sugar-loaf. 



Confluent, running together. 



Conoid, a fissure like a cone, sugar- 

 loaf-shaped. 



Contorted, twisted, or incumbent on 

 each other, in an oblique direction. 



Contracted, shortened, shrunk up. 



Convoluted, rolled upon itself, twisted 

 spirally, like a piece of paper rolled 

 between the finger and thumb. 



Cordate, heart-shaped. 



Cordiforin, resembling the form of a 

 heart. 



Coriaceous, of a leather-like consist- 

 ence. 



Corneous, of a horn colour, resembling 

 a horn. 



Coronal, relating to the crown or 

 top. 



Coronated, crowned, or girt towards 

 the apex. 



Costated, ribbed, having large ribs. 



Corpus, the body of the shell, the last 

 or great wreath in which the aper- 

 ture is situate. 



Cortex, the anterior skin or epider- 

 mis. 



Crenulated, notched At the margin, 

 scalloped. 



Crispated, rough with waving lines. 



Cuneiform, shaped like a wedge. 



Cylindrical, round like a cylinder or 

 a roller. 



Cymbyform, boat-shaped. 

 D. 



Decorticated, worn, divested of epi- 

 dermis or skin. 



Decussated, generally applied to striae, 

 or lines, which are crossed, or which 

 intersect each other perpendicularly 

 or horizontally. 



Deflexed, bent aside. 



Dentary, of or belonging to the teeth. 



Dentile, a small tooth, such as the 

 tooth of a saw. 



Denticulated, set with small teeth, as 

 in the A;ca. 



Depressed, pressed down horizontally, 

 low, shallow, flat. 



Dexter valve, is the right valve. 



Diaphanous, transparent, clear, pel- 

 lucid. 



Digitated, fingered or clawed, as in 

 the lobes ot the outer lip of the 

 Strombi, &c. 



Disk, the middle part of the valves or 

 that which lies between the umbo 

 and the margin. 



Divaricated, straddling, spreading out 

 widely. 



Divergent, tending to various parts 

 or directions from one point. 



Dorsum, the back, it generally means 

 the upper surface of the body of the 

 shell, when laid upon tlie aperture 

 or opening. In the genera of Pa- 

 tella and Haliotis, the back means 

 the upper convex surface. 



Dotted, punctured like a thimble. 



Duplicated, divided into plaits or 

 folds. 



Duplicature, a fold, any thing doubled. 



Echinated, bristled like ahog, set with 

 spines. 



Ettuse, spread out. 



Elliptical, having the form of an ellip- 

 sis, oval. 



Elongated, lengthened, drawn out. 



Emarginate, Iwith the margin or 



Emarginated, 5 edge notched. 



Ensiform, sabre-shaped. 



Entire, whole, uninterrupted, notdi- 

 vided. 



Epidermis, the outer coating or scarf 

 skin of the shell. 



Equidistant, being at the same dis- 

 tance. 



Equilateral, having all sides alike. 



Equivalve, having both valves of 

 equal dimensions. 



Exolete, worn or faded. 



Exserted, standing out, protruding. 



Extraneous, not belonging to a par- 

 ticular thing. 



