8 



.- ( irayish-whitr. 

 Si/.,-. Len-th about rjmm.; hivadlh ~> mm. ; hriirhi 



inin. 



s . Fornmi- a short po-terior nw, ^i\ <.r seven in number. 



This species is considerably lar-er and OOartOT than tin- |>i 



(L. benthut'). The tubercles are twice the size and <! ther, 



The shell IB also Comparatively >harply keel.-d, instead of having a 

 uvntlv rounded appearance. 



L. BEVTHU6 Haddon. IM. 1, ligs. 1-13. 



Shell. Delicate, brittle, surface with minute inc.,n^,i(MiMUs >ln.rt 

 ridges more or less radially disposed, and studded with small tul.er- 

 cles 3 . The sides meet at a rounded angle of about 100. Sntural 

 lamina- small. 



Anterior valve. With minute scattered tubercles, which | 

 towards the apex into low tubercular ridges, having a concentric 

 arrangement. 



Intermediate valves. Central areas: The minute surface ridges, 

 when visible, are longitudinally disposed on the jugum, but be. 

 radial or oblique on the pleura. The tubercles are round on the 

 jugum, but becomeVomewhat oval on the pleura, and there appear 

 to & be concentrically arranged, although in some valves they seem 

 to more or less regularly diverge from the apex. Lateral areas : 

 The surface ridges are radial and more pronounced than elsewhere. 

 On the upper portion of the areas there are transverse low ri 

 placed further apart than the former ; these ridges by bein- inter- 

 rupted gradually pass into tubercles. The tubercles are round, 

 distinctly smaller than in the central areas, and more scattered. 



Posterior valve. With a small central umbo. Anterior an a : 

 With concentric tubercles, as in the lateral areas. Posterior area : 

 Similar to the anterior valve. 



Qi r jl e .__N arroWj with delicate scales, which form a minute fri 

 at the edge. 



C l olv _Greenish-white with one or two irregular reddish-brown 



flecks. 



Size. Length, 8 mm. ; breadth, 3.."> mm. 



Northern 7V//.V, Lt. 35 41' N., long. 157 4? K.. i.. 2300 fas. 



/.. henthus HAD., ('hall. K.-p. xv, p. H>, t. 1. f. 1. t. 2, f. 



dills. Seven in number, extending between the prominent anu> 

 and postero-lateral angle of the foot. The gill row ifl ..n.venth 



