228 MALACOZOA. THOPIOPODA. LAMELLIBR AXCHIATA, 



First found in tlie Winter of 1S41, b}- Mr. L-eslie, at Aber- 

 deen and the Cove. 



Pecten siiiiilis. Laskev, Wem. Mem. i. 387. PI. 8. f. 8, 8.— 

 Pecten similis. Flem. Brit. Anim. 385. 



11. Pecten tihnidus. Unequal-sided Scallop, 



Shell suborbicular, flattish, thin, fragile, smooth, semitrans- 

 parent tovrard the margins, opaque-white in the centre ; the 

 valves almost equal, with one side bulging ; mnbones nearly 

 centi-al, pointed, hinge-line straight ; auricles about equal in 

 length, smooth, being but faintly marked with gjowth-lines ; 

 colour white. Diameter a quarter of an inch. 



This species can hardly be confomided with either of the 

 two last, unless b}- persons who may suspect all little smooth 

 pectens to be the same. All the specimens seen by me have 

 an opaque white central portion, the margin ti'ansparent, the 

 smafl auricle of the upper valve rounded, the auricles not 

 striated longitudinally, and one of the sides very prominent. 

 Small specimens of the same size as Turton's figure agree per- 

 fectly with it, and, although the circimistance is not mentioned 

 in the description, it will be seen to be white in the centre. 



First fomid by !Mr. Alexander Da\'idson m the stomach of 

 a haddock, Aberdeen, in the Winter of 1841 ; by me, on the 

 beach there, in October, 1842. 



Genus 2. Lima. Rasp-Scallop. 



Shell free, regular, oval or oblong, equivalve, aniso- 

 meral, divergently costulate or striate; umbones very 

 small, pointed, direct, not contiguous. Cardinal space 

 elongated, with a straight margin, and hanng externally 

 a somewhat triangular concave depression. Ligament 

 external, trigonal, received by the cardinal pits. 



1. Lima Loscomhi. Loscombe's Rasp-Scallop. 



Shell obhquely oval-oblong, tmnid, thin, brittle, pellucid ; 

 with the hinge auricidate ; the umbones small, projecting a 

 httle beyond the margin ; the valves equal, with tine concen- 

 tric striulae, and numerous slightly undulated, radiating cos- 

 tulee, with intervening striae, generally two or three between 

 each pair ; the colour hyahne-white ; the inside glossy, with 

 the radiating markings apparent. Length in the direction 



