12 LEPIDOPLEURUS. 



of longitudinal subgranose striae. Mucro subcentral and prominent. 

 The lateral areas are slightly raised. 



Length 13-14, breadth 7 mill. ; divergence 100. 



Monterey, Cal., to Todos Santos Say, L. California. 



L. (f internexus var.} rugatus CPU. MS., p. 3. 



This form resembles somewhat the L. granoliratus, but it is much 

 more finely sculptured, the arch of the valves is narrower and the 

 lateral areas are less strongly marked by concentric wrinkles. It 

 is likely that the following is merely the young of this, but I have 

 not been able to compare typical specimens of internexus. 



L. INTERNEXUS Carpenter. 



Shell similar to L. nexus, but much smaller, orange colored. 

 Valves regularly arcuate, without jugum. Sutural plates small, 

 triangular; sinus larger. Girdle with more solid scales, scarcely 

 pilose. (Cpr.) Length 4i, breadth 31 mill.; div. 90. 



Santa Barbara, California. 

 L. internexus CPR. MS., p. 3. 



L. KERGUELENSIS Haddon. PL 1, figs. 14-17. 



Shell. Minute, smooth, or with scattered minute tubercles ; the 

 sides meet at an angle of about 100 ; sutural laminae small, tri- 

 angular. 



Anterior valve. Small, smooth, with scattered aborted tubercles. 



Intermediate valves. Central area smooth, with very faint longi- 

 tudinal striae; lateral areas scarcely discernible, with faint radial 

 striae and minute concentric interrupted ridges towards the apex, 

 which pass into inconspicuous small scattered tubercles. 



Posterior valve. With full rounded umbo, behind which is a 

 shallow depression. Anterior area: similar to the central areas of 

 the intermediate valves. Posterior area similar to the anterior 

 valve. 



Girdle. Narrow, with delicate scales. 



Color. Uniform whitish. 



Size. Length 3, breadth 1*5 mill. 



Gills. Posterior, eight or nine in number (Haddon.) 



Balfour Bay, Royal Sound, Kerguelen, 60 fms. 



L. kerguelensis HAD., Challenger Kep. xv, p. 12, t. 1, f. 3 ; t. 2, f. 

 3a-3e. 



L. PAGENSTECHERI Pfeffer. PI. 2, figs. 39-40. 



Shell elevated, roof-shaped, with the dorsal angle rounded ; 

 covered with a fine, indistinct, irregular granulation, without dif- 



