MAZATLAN UNIVALVES 215 



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

 the middle. 



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

 ribs strong. Inside white witliin 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 ctuoted above ; and closely resembles F. Barbadensis. 



[272. FissuEELLA Baebadensis, Gmel. 



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



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



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



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

 Patella perforata, Dillw. Descr. Cat. p. 1558, no. 95. 

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



no. 9 : et auct. 

 Cremides Barbadensis, H. Sf 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, 

 Sah. — Cuba, Sagm. — Barbadoes, Lamarck et auct. — Mazatlan; 



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



Tablet 1038 contains the specimen.] 



273. FiSSUEELLA BTJGOSA, SotO. 



F. t. maxime variante ; ijlerumiqm costis plus minusve cBquali- 

 bus, interdum nodulosis, intet'dtim quihusdam alteras maxime 

 superantibus ; margine valde irregulari, interdum ovali, inter- 

 dum elongato, plerumqiie antice angulato, a costis plus mimisve 

 crenato ; aperturd liaud centrali ; seu subcirculari, ovata ; sett 

 oblongiv, medio constrictd; seu bilobata; seu trilobatd; seu lineari, 

 ad extremitates lobatd : callositate plus minusve extante, seu 

 co^ncolore, seu lined, purpurea cinctd ; superjieie externa rubro- 

 olivaced, seu rubra, seu cinered, ; interna vireseente, interdum 

 rubro plus minusve maculatd ; formd plerumque planatd, inter- 

 dum. subconicd. 



Conch, m. sp. 66, f. hi.— Eve. Conch. Icon. pi. 8, f. 56. (Diagn. 

 auct.) 



