ii PIBOPL1 iKUS. 1 1 



L. CONCINNU8 Gould. I'njif/nrnL 



Shell minute, reddish, elliptical, vaulted, all over punctate [ LM 



lose], the points arranged in radiating, nirvmi: B6rie0; lateral areas 

 hardly elevated, longitudinally waved, l-'mut valve oretoentlC : 

 posterior valve with an acute umbo, concentrically waved. < ,'mlle 

 narrow, buff. (Old.) Length 8, breadth r, mill. 



Butural plates small, subtriangular ; jugal sinus very wide, flat ; 

 scales of the girdle delicate. (Qpr.) 



Hakodadi, Japan, laminarian zone, on shells and 



C. (Leptochiton) concinnus GLD., Otia Conch, p. 117. Lepto- 

 chiton concinnus CPR. MS., p. 3. DALL, Proc. U. S. Nat. Mu~. p. 

 318, 316, 1878. 



L. NEXUS Carpenter. Unfigured. 



Shell small, whitish-ashen, valves gothic-arched ; lateral areas 

 scarcely defined; entire surface ornamented with series of sulujuad- 

 rate granules, the series longitudinal upon the central, radiating 

 upon the lateral areas and end valves, very close, scarcely inter- 

 rupted. Jugum elevated, subacute; umbones inconspicuous. Mucn. 

 conspicuous, median. Inside with strong sutural lobes and a wide 

 plane sinus to the middle valves; insertion plates obsolete. Girdle 

 having narrow, close, striated scales and needle-shaped, crystalline 

 bristles here and there and around the margin. (Q?r.) 



Length 7s, breadth 4 mill.; div. 90. 



Catalina Island, California, 20-80 fins. 



Leptochiton nexus CPR., Rep. Brit. Asso. Adv. Sci. for 1863, p. 

 650,1864; Proc. Cal. Acad. iii, p. 212, 1866; ms. p. 2. DAM.. 

 Proc. U. S. Nat. Mus. 1878, p. 316, 319. 



A variety is prettily variegated with olive, has stronger sculpt- 

 ure, and the valves slightly beaked. The spicules which appear on 

 the girdle among the striated, elongated scales, are very numerous. 

 It is curiously like the young of Ischnochiton radians. (Cpr.} 



See notes under L. cancellatus for comparison with that species. 



L. RUGATUS Carpenter, n. sp. PI. 3, figs. 67-70. 



Oval, rather convex, the lateral slopes nearly straight, doi-al 

 ridge broadly arched. Front and back valves and lateral areas of 

 the intermediate valves sculptured with excessively fine radiating 

 striae which are feebly granose, and having well-marked, coarse, con- 

 centric wrinkles; central areas having an equally minute sculpture 



