OF CONCHOLOGY. 141 



Subgenus Lepeta, Dall ex Gray. 



. Gen. eh. — Apex erect ; shell slightly colored, or uncolored, 

 sculpture more or less strongly striate, reticulate or papillose. 

 Mantle edge entire, simple. Tentacles setaceous. Rhachidian 

 tooth tricuspid, central cusp much larger than the other two ; 

 shape rhomboidal. Laterals broadly simply cuspidate, pointed 

 at their bases. 



Ti/pe. Lepeta c^ca, Gray. Plate 15, fig. 1, a, b, c, d. 



JSpi. n Patella cceca, 0. F. Muller, Pr. Z. Danica 1766, p. 



237 ; Zool. Dan. vol. i, p. 25. 

 Patella cceca, Loven, Ov. K. v. Ak. For. p. 199, pi. vi, 



1847. 

 ?? Patella cceca, var. genuina, Midd., Bull. Phys. Math. 



Ac. Sci. St. Petersb. vol. vi, No. 20, 1847 ; Sib. Reise, 



p. 183, pi. xvi, fig. 6. 

 ?? Lepeta ca^ca, Gray, P. Z. S. 1847, p. 168 ; Guide Moll. 



p. J72, fig. 103. H. and A. Adams, Gen. Rec. Moll. 



vol. i, p. 462 (not fig.) Jeffries, Brit. Conch, vol. iii, 



p. 251, pi. 5, fig. 6. 

 Patella cerea, MoUer, Moll. Gronl. p. 16. 

 Patella Candida, Couthouy, Best. Jour. Nat. History, vol. 



ii, p. 86, pi. iii, fig. 17, Feb. 1838. Gould, Inv. Mass. 



p. 152, 1841. 

 Pilidium candidum, Stimpson, Shells of New England, p. 



29, 1851. 

 ? Lepeta Franklini,'^ Gray, Guide Moll. p. 172. 

 Not Propilidium ancyloide of Forbes and Hanley, as 



afiirm Gray, Guide Moll. p. 172, and H. and A. 



Adams, Geia. Rec. Moll. vol. i, p. 462. 



Sp. ch. — Shell patelliform. Apex erect, situated in the cen- 

 tral third. Nucleus sinistral, deciduous. Sculpture fine radiating 

 elevated striae, rendered nodulous by the intersection of imbri- 

 cated concentric lines of growth, forming a beautifully reticulated 

 series of papillse, stronger toward the base. Anterior and pos- 

 terior planes sometimes arched, often straight, and very frequent- 

 ly somewhat concave, giving a peculiar prominence to the apex, 

 which is generally eroded. Color white, generally concealed by 

 a brown epidermis, and sometimes having a pinkish or rufous 

 tinge. Shape somewhat elongate oval. Long. -45, lat. '34, 

 alt. -22 in. Defl. 100°. Number examined, 38 specimens. 



* In none of the works at hand on the Mollusca can I find any other 

 reference to this (? described) species than the original one of Dr. Gray. 

 1 therefore place it doubtfully in the synonymy of this species. 



