382 TELLINID.E. 



5. T. fa'bula*, Gronovius. 



T.fabula, Gron. Zoophyl. iii. p. 268, t. 18. f. 9 ; F. & H. i. p. 302. pi. six. 

 f. 9. 



Body clear white : tubes apparently rather longer than in 

 T. tenuis, which the animal closely resembles (Forbes and 

 Hanley). 



Shell triangularly oval or inclining to oblong, flattened, 

 thin, semitransparent, glossy, and having a resplendent and 

 prismatic lustre: sculpture, extremely fine, numerous, and 

 sharply incised concentric striae, which in the right valve are 

 at first regular and parallel, but afterwards become stronger, 

 more remote, imbricated, and flexuous, and slant diagonally 

 from the upper part of the anterior side towards the front and 

 posterior margin ; the surface is also covered with much more 

 numerous and close-set microscopical transverse striae, as well 

 as with a few slight longitudinal lines, as in the last species ; 

 the posterior side (and occasionally the anterior side also) is 

 not marked by the larger striae ; the lines of growth are well 

 defined and sometimes form distinct zones : colour pearl-white 

 with frequently a tinge of yellow or occasionally of light 

 orange : epidermis very thin and brilliantly iridescent : mar- 

 gins not much curved in front, semioval on the anterior side, 

 flexuous on the posterior side and elongated to a rather sharp 

 point, from which an obscure ridge runs to the beaks as in 

 T. tenuis ; the posterior margin is short and obliquely trun- 

 cate ; the dorsal margin is more or less straight, and slopes to 

 the upper angle of the posterior side : beaks small, scarcely in- 

 flected, contiguous, and turned a little towards the posterior 

 side : ligament as in the last species : hinge-line and hinge- 

 plate also similar : teeth, in the right valve two erect, small, 

 deeply cloven cardinals ; in the left valve a cardinal of the 

 same kind just under the beak, and a much smaller and 

 laminar cardinal on the posterior side, which diverges from 

 the other at about a right angle ; each valve has a short in- 

 distinct lateral on the anterior side : inside chalky- white, 

 except the line of the pallia! scar and the whole of the mus- 

 cular scars, which are polished : pallial scar as in the last two 

 species, but larger, with the upper angle extending much fur- 

 ther towards the beak, and infringing on the posterior mus- 

 cular impression: muscular scars irregular, but distinct and 

 visible outside. L. 0-5. B. 0-85. 



* A small bean. 



