TELLINA. 293 



exterior, which is not lustrous, is yet occasionally glossy, 

 and densely striated in both valves with concentric and 

 subimhricated lines, one half of which disappear on reach- 

 ing the umbonal fold. The ordinary colouring consists of 

 very numerous interrupted rays of a carnation red upon a 

 whitish or yellowish ground, with the environs of the liga- 

 ment, the inflected hinder dorsal area (which is narrow or 

 even linear), and a short direct ray which emanates from 

 behind the beaks, all stained with the same brilliant dye. 

 Not unfrequently, also, the surface is zoned with lighter 

 and darker shades of pink or yellow. We have figured 

 likewise a beautiful and uncommon variety (from Portland) 

 in which the ground colour is crimson, and the rays, zones, 

 and apices are white. The ventral margin which exhibits the 

 generic flexuosity (the curvature of the posterior side to the 

 right being very distinct) is comparatively straight behind, 

 but arches out moderately in front where it very obliquely 

 ascends in an uninterrupted sweep to the dorsal edge, which 

 being scarcely convex, barely declining, and much pro- 

 duced, the anterior extremity (although the tip is arched) 

 is not rounded symmetrically, and the chief swell is above 

 and not beneath the middle. The posterior side, which is 

 scarcely half the length of the anterior one, is abbreviatedly 

 wedge-shaped, as the hinder dorsal margin rather abruptly 

 declines in a straightish line, which however becomes convex 

 near its termination, thus rounding oif the posterior tip. 

 The ligament is large and prominent. The interior is 

 either stained with rich yellow, displaying the rosy apical 

 ray and the dorsal stains, or faintly exhibits the external 

 colouring. The hinge of the right valve is furnished, in 

 addition to its primary teeth, with two lateral laminse, of 

 which the front one is decidedly the larger and the more 

 approximate. 



