SOLEN. 15 



white to brownish-yellow : mantle thick, protruded a little 

 beyond the valves of the shell ; edges plain : tubes contiguous 

 and nearly sessile; orifice of each fringed with tentacles or 

 cirri of different lengths, which are spotted with yellow or 

 flake -white : gills unequal in ^ size, the upper pair not being 

 half the depth of the lower pair : pcdj^s small, smooth outside 

 and pectinated within : foot tongue-shaped and flexible, lying 

 when at rest across the shell on the anterior side : liver green. 



Shell usually sabre-shaped, but of various degrees of curva- 

 ture, tapering to each extremity, scarcely transparent except 

 in young specimens, glossy and partiallj^ iridescent : sculpture^ 

 numerous and fine but irregular striae in the line of growth, 

 and a few slight and minute longitudinal striae in the middle, 

 which radiate from the beaks to the front : colour yellowish- 

 white, with sometimes faint transverse streaks of salmon- 

 colour : epidei'mis like oil-skin, yellowish-green or hght 

 orange, puckered by the radiating striae : margins gently curved 

 in front and almost straight behind, rounded at the anterior 

 end, and obliquely truncated at the other end ; dorsal area 

 apparently separated from the ventral part, in consequence of 

 the epidermis being thinner and of a paler hue behind : heahs 

 inconspicuous, incHning a little to the anterior side, which they 

 approach within one-fifth of the whole distance : ligament 

 lanceolate, yellowish-brown : hinge-line straight : hinge-plate 

 short, strengthened in each valve by a sHght rib to support 

 the ligament, and by a short and thicker rib at the other 

 end, which diverges inside towards the front anterior margin : 

 teeth somewhat irregular; in the right valve an erect and 

 wedge-like cardinal, and in the left two similar cardinals, 

 which resemble a pair of nippers ; the posterior cardinal in the 

 left valve is often branched or forked ; each valve has a lateral 

 at no great distance from the cardinal teeth, of an irregular 

 shape, and bent towards each other, that in the right valve 

 being occasionally double : inside polished ; margin sharp : 

 scars indistinct; pallial sinus short. L. 0-4. B. 1-5. 



Habitat : Gregarious in various parts of the British 

 seas, in sand (often mixed with mud), at depths of from 

 4 to 85 f. In a fossil state it occurs at Belfast and 

 in the Coralline Crag ; and Philippi appears to have 

 recorded it from Palermo "^^ under the name of S. tenuis. 



* In the preceding volume of this work I inadvertently mentioned 



