MAZATLAN BIVALVES 93 



126. CaEDIUM ? SEXTICOSXJM, Soio. 



Proc. Zool. Sor. 1833, p. SL—Mllll. Spi. Test. Viv. p. 218.— 

 Sow. Conch. III. no. 43, pi. 47, f. IQ.—Rve. Conch. Sj/st. pi. 74, 

 i. 10 -.—Conch. 7(>. Ind. Card. & Errata.— ^rtH7. Descr. Cat. 

 p. 137.— B. M. Cat. D'Orh. Moll. p. 74, no. 658.-0. B. Ad. 

 Pan. Shells, p. 268, no. 434. 

 = Cardium rastrum, Rve. Conch. Ic. pi. 16, f. 82.* 

 ? = Cardiiim muricatum, Menke in Zeit. f. Mai. 1847, p. 188. 

 no. 50. 



Tablet 454 contains a nearly perfect minute valve and 6 frag- 

 ments of larger shells, whick probably belong to this species. 

 The ribs are extremely close, about 40, and bearing traces of 

 grains which are strongest on the anterior side. The smallest 

 fragment has a fine line running down the interstices, which is 

 probably an accidental variety, as I have a specimen of C. 

 echinatum displaying the same structure. C. muricatum is 

 the West Indian analogue. 



H'alj.—St. Elena, in sandy mud, 6-12 fm. Cum/ n{/.— 'Ecuador ; 

 St. Elena, D' Orljic/n?/.—Tahoga ; very rare ; C. B. Adams.— 

 ? Mazatlan ; extremely rare, in shell washings ; L'pool Cvl. 



127. Caedium sp. ind. (a.) 



C. t. fjiin. minimd, orbiculari, costis cirdter xl. approxima- 

 tis, haud extantihus, graniferis ; superficie tot a minutis- 

 sime quasi arenatd, dentibus lateralihus hand magtiis. 



Two valves and a fragment only were foxmd of this shell, 

 differing from C. punctulatum, Brod. Si' Soto.. Zool. Journ. 

 vol. iv. p. 366, in the characters above named. The entire 

 surface appears as though dusted over with grains of sand. 

 It appears to be a young shell : if the adult, when found, have 

 the same characters, it may take the name of C. areuatum. 

 Long. -08, lat. "08, alt. '06. 



^oi.— Mazatlan ; from Spondylus washings ; extremely rare ; 

 L'pool Col. 



Tablet 455 contains a nearly perfect valve. 



* "-^I'; ^e«"'« ';'ifr"n« to P. Z. S. 1811 for Sowerby's description is evidently 

 a misprint for 1833 ; and the reference to the same work, 1845. for C rastrum 

 seems erroneous Mr HanJey's reference to Eeeve Conch. Syst. pi. 84 is also a 

 misprint for 74." C. £. Adams, he. cit. 



