MAZATIAN BIVALVES 105 



tinidae. Tlie genera also are by no means satisfactorily ascer- 

 tained ; the same shell having been described by Forbes and 

 Hanley as Kellia nitida and Leptou convexum ; v. Br. Moll. 

 vol. iv., app. p. 255. As the animals of the Mazatlan species 

 are entirely unknown, a systematic arrangement of them is 

 not attempted ; and they are simply grouped under genera 

 according to the preponderance of characters. 



GENtJs KELLIA, Turt. 



Kellia, Turton Conch. Dyth. Brit. 1822, p. 56. 

 Erycina, Payr. non Lam. (sp.) 

 Chironia (Laperousii) Desk. Rev. Zool. 1839, p. 356. 

 Bornia, sp., PhiUppi, Enum. Moll. Sic. 1836, p. 13. 

 TelLimya, sp., Brown, HI. Conch. Gr. Br. 



153. Kellia suboebiculaeis, Mont. 



Mya suborbicularis, Mo>it. Test. Brit. pp. 39, 564, pi. 26, f. 6. 



Tellina suborbicularis, Turt. Conch. Diet. p. 179. 



Eellia suborbicularis, Turt. Dith. Brit. p. 56, pi. 11, f. 5, 6. — 

 Alder, Cat. North. 8f Durh. 31oll. p. QZ.— Forbes Sf Sard. 

 Br. Moll. vol. ii. p. 87, pi. 18, f 9, %a, 95, pi. O, f. ^.—SearUs 

 Wood, Crag. Moll. (PalfEont. Soc.) Part ii. p. 118, pi. 12, 

 f. 8, a, h. Clarh Moll. Test. Mar. Brit. p. 89. 



Petricola suborbicularis. Gray, Ann. Phil. 1825. 



Erycina suborbicularis. Bed. Rev. Zool. 1844. 



Tellimya suborbicularis. Brown, III. Conch. Gr. Br. ed. 2, 

 p. 106, pi. 43, f. 14, 15. 



+ Tellimya tenuis. Brown, loc. cit. f. 12, 13. 



? + Tellimya lactea, Broion, loc. cit. f. 10, 11.— (Kellia 1.) B. M. 

 Cat. Br. Moll. pt. 7, p. 83, no. 'i.—Loven, I. M. 44, 310. 



Erycina Geoffroyii, Payr. Cors. 30, pi. 1, f. 3—5. 



Amphidesma physoides. Lam. fide Sow..* 



Bornia inflata, Phil. Moll. Sic. vol. i. p. 14, & vol. ii. p. 11. 



After often repeated and most careful examinations of many 

 hundred specimens, comparing them -with each other and with 

 the very minute description in the Br. Moll, as well as with 

 every Atlantic specimen that has been accessible, I am unable 

 to give any specific characters by which the Mazatlan sheUs 



• A. physoides, Lam. Erycina ph. Deiih. The description of this shell 

 (An. ». Vert. ed. De»k. vi. 130, no. 16,^ will fit any similar species. "A. t. orbi- 

 culato-globosa, byalina, vesiculari. Hab. au port "da roi George. Peron." 



