342 venerid^:. 



D. Mantle-tubes disunited only at their openings. Shell oval, 

 ornamented with longitudinal ribs and cross stria), giving 

 partly a tubercular and partly an imbricated appearance ; 

 inside margin notched all round. 



7. V. ova'ta*, Pennant. 



V. ovata, Perm. Brit. Zool. iv. p. 97, pi. 56. f. 56; F. & H. i. p. 419, pi. xxiv. 

 f. 2, pi. xxvi. f. 1, and (animal) pi. L. f. 6. 



Body suboval, bluish-white interspersed with minute flakes 

 of milk-white or yellow : mantle with thickened edges, which 

 are wavy and fringed by numerous white filaments of different 

 lengths : tubes very short, of the same, length, yellow, united 

 except at the openings, where they diverge a little and are 

 encircled with a row of reddish-brown spots ; lips of orifices 

 slightly reflected, and surrounded by purplish or pale-yellow 

 tentacular cirri, each orifice having about 20 of these cirri, 

 which are alternately long and short, and each cirrus having 

 a coloured spot at its base ; the excurrent tube is furnished 

 with the usual anal valve : gills suboval, very oblique, pale 

 yellow or brown, more striated on the inner than on the outer 

 surface : palps short, small, triangular, and striated like the 

 gills : foot very long, thick, flexible and extensile, protruded 

 with equal facility on the anterior or posterior side. 



Shell triangularly oval, rather solid and opaque, of a dull 

 aspect: sculpture, 40-50 fine but rather broad ribs, which 

 radiate from the beak and more or less dichotomize or branch 

 off in different parts ; these ribs are crossed by about half as 

 many more raised and thread-like concentric strise, and, in 

 consequence of their intersection, a series of oblong tubercles 

 or imbricated scales crests each rib ; the cross strise are often 

 wanting on the front angle of the posterior side ; the whole 

 surface is also covered with minute and intermediate trans- 

 verse striae, which are stronger and more perceptible in the 

 furrows : colour yellowish, with occasionally a tinge of pink or 

 orange variegated by irregular blotches, broken rays, or van- 

 dyke markings of red dish -brown: epidermis fibrous and slight : 

 margins rounded on the anterior side, with a blunter curve in 

 front, wedge-shaped and somewhat produced at the posterior 

 end, on which side an obscure angle appears to run from the 

 beak, and gently sloping on the dorsal side : beaks small and 

 blunt, rather prominent but not much recurved or separated : 



* Egg-shaped. 



