278 MAZATLAN UNIVALVES 
2 Cr. incurva in situ, one on the other.—1380, 2 sp. with 
Bryozoa and Serpula. 
Aberrant specimens. Tablet 1381 contains 2 sp. deck thin, as 
in C. nivea.—1382, 1 sp. very convex, light coloured.—1383, 
2 sp. deck variable in length.—1384, 5 sp. margin irregular.— 
1385, 4 do. diseased.—1386, 3. sp. form approaching C. adunca, 
jun.—1387, 5 do. adult. 
340. CREPIDULA ONYX, Sow. 
C. t. solidiore, plerumque lamellis, ad marginem sepe, extus 
rare apparentibus, tnstructa ; epidermide olivaced copiose in- 
duta, irregulariter lamellosé, haud nitente ; habitu inerementi 
plerumque recto, sew incurvato, haud spirals ; planaté, seu in- 
 terdum convexd ; colore hepatico, splendente, interdum nigriore, 
rare livido-carneo ; vertice niicleoso parvo, levi, discoidali, apice 
celato, prope marginem plerumque centraliter sito, sepissime ad 
marginem veeto et detrito; test&é jguniore subcorned, castaneo 
maculata, haud nigra ; septo interno solidiore, opaco, albo, 
striulas tmcrementi nist marginem versus haud monstrante, 
margine plus minusve tntus angulato, nec antice nec postice 
distincte sinuato. 
Sow. Gen. Crepidula, f. 2. 
Crypta onyx, H. & A. Ad. Gen. i. p. 369. 
=Crepidula ? hepatica, C. B. Ad. Pan. Shells, p. 227, no. 346. 
(teste sp. typ. in Mus. Cum.): non Menke in Zeit. f Mal. 
1847, p. 184, no. 33. 
rE Crepidula hepatica, Desh. Ene. Meth. Vers, 1830, peak ite 
Duco, NO:7 : eee An. s. Vert. vol. vu. p. 646, no. 12.— 
(Crepipatella h.) H. & A. Ad. Gen. i. 369. 
P=Crepidula hepatica, Krauss Sudafr. Moll. p. 69, no. 3, pl. 4, 
f. 12 a, b.— Dkr. Ind. Moll. Guin. p. 34, no. 92 pl. 5 i 4, 5. 
= ae amyegdalus, Val. Voy. Ven. pl. 15, f 3. 4/3 
Var. ?=Crepidula contorta, Mike. Zeit. f. Mal. 1851, 305 
no. 121, (non Quoy J Gaim.) 
Jun.=Crepidula Cerithicola, C. B. Ad. Pan. Shells, pp. 225, 
320, no. 343. 
Comp. Crepidula rugosa, Nutt. in Jay’s Cat. p. 107, no. 3043, dis.- 
Proc. Zool. Soc. 1856.—(Crypta.r.) H. & A. Ad. Gen. i. 369. 
Whether Deshayes described his C. hepatica from a Pacific or 
African shellis not known; and whether the two are identical 
has not yet been ascertained, the African speeimens being 
generally too much worn for comparison. Krauss’ var. com- 
