MAZATLAN UNIVALVES 215 



Tablet 1036 contains a sp. with the hole not constricted in 

 the middle. 



Tablet 1037 contains a sp. with a circular hole. Nodulous 

 ribs strong. Inside white within the muscular scar, and at 

 the margin. In other respects like the typical form. It would 

 have passed for a distinct species, but for the intermediate 

 form quoted above ; and closely resembles F. Barbadensis. 



[272. FISSTJEELLA BAEBADENSIS, Gmel. 



Patella Barbadensis, Gmel. p. 3729, no." 199 : + P. perforata, 



Gmel. p. 3730, no. 202 : +P. porphyrozonias, Gmel. p. 3730 ; 



Dillw. p. 1061, no. 102 : + P. rosea, Gmel. p. 3730 ; teste 



B. M. Cat. Cub. Moll. p. 33, no. 400. 

 Patella perforata, Dillw. Descr. Cat. p. 155.8, no. 95. 

 Fissurella Barbadensis, Lam. An. s. Vert. vol. vii. p. 595, 



no. 9 : et auct. 

 Cremides Barbadensis, H. A. Ad. Gen. i. 446. 



One small specimen of this well known West Indian species 

 was found, which might have been taken for an extreme variety 

 of F. rugosa, were it not for an abundance of the Spiroglyphus, 

 and a trace of the red coral, both of which are characteristic of 

 the Atlantic ocean, and are entirely absent from the genuine 

 Mazatlan shells. It is perfectly fresh, and probably came over 

 on a pebble as ballast. 

 Hob. Cuba, Sagra. Barbadoes, Lamarck, et auct. Mazatlan; 



1 small specimen, ? imported in ballast ; L'pool Col. 



Tablet 1038 contains the specimen.] 



I 273. FISSUEELLA EUGOSA, Sow. 



F. t. maxime variante ; plerumque costis plus minusve ceguaU- 

 bus, interdum nodulosis, interdum quibusdam alteras maxime 

 superantibus ; margine valde irregulari, interdum ovali, inter- 

 dum elongato, plerumque ant ice angulato, a costis plus minusve 

 crenato ; aperturd haud centrali ; sen subcirculari^ ovatd ; seu 

 oblongd, media constrictd; seu bilobatd; seu trilobatd; seu lineari, 

 ad extremitates lobatd : callositate plus minusve extante, seu 

 concolore, seu lined purpured cinctd ; superficie externd rubro- 

 olivaced, sen rubrd, seu cinered ; internd virescente, interdum 

 rubro plus minusve maculatd ; formd plerumque planatd, inter- 

 dum subconicd. 

 Conch. III. sp. 66, f. 54>.Itve. Conch, Icon. pL 8, f. 56. (Diagn. 



auct.) 



