

166 FISSURELLA. 



riblets, every fourth one a little larger. Fissure nearly round. 

 Inside light green, having a dull reddish line around the central 

 callus, and sometimes mottled with pink outside of the muscle im- 

 pression. Border finely crenulated. 



Length 21, breadth 15, alt. 8 mill.; number of radiating riblet& 

 about 60. 



Length 16?, breadth 12, alt. 7 mill. ; number of riblets 40. 



St. Thomas; Bermuda. 



The St. Thomas specimen is larger and has more riblets than 

 those from Bermuda, and it is more variegated inside with pink. 

 It is the one figured. The Bermuda shells, which may be regarded 

 as typical, have the orifice a little larger. They were collected by 

 Professor Angelo Heilprin. 



F. ROSEA Gmelin. PI. 62, figs. 19, 20, 21. 



Shell conical, oblong-ovate, narrower in front, the apex a little in 

 front of the middle of the shell. Sculptured with numerous unequal 

 rounded radiating riblets, sometimes scaly. Grayish, having 10 to 

 12 broad red or purple rays. Perforation oval, small, its length one- 

 ninth to one-twelfth the length of the shell. 



The outline is about as in F. nubecula of European seas. Altitude 

 quite variable, generally one-half the breadth or a little less. Ribs 

 more prominent than in F. nubecula. Interior uniform green or 

 with a white tract not extending outward as far as the muscle im- 

 pression. Hole-callus bounded by a red line. Border a little cren- 

 ulated. Muscle-impression rather wide, not distinct or impressed. 



Length 26, breadth 16, alt. 8, mill. ; length of hole 2 mill. 



Length 26, breadth 16J, alt. 6, mill. ; length of hole 2i mill. 



Length 24, breadth 15 J, alt. 7, mill. ; length of hole 2 mill. 



Matanzas, Cuba ; Vera Cruz, Mexico ; Costa Rica ; Guiana, and 

 Rio Janeiro. 



Patella rosea GMEL. Syst. Nat. xiii, p. 3730. F. rosea LAMARCK, 

 An. s. Vert, vi, 2d. pt., p. 12. SOWB., Thes. Conch, iii, p. 190, f. 

 91, 92, 150. 



This species seems to be abundant along the coast of the main- 

 land of America from Vera Cruz (Heilprin, 1890) southward to 

 Costa Rica (Gabb), and specimens are also before me from Guiana 

 and Rio Janeiro. I have above pointed out the differences between 

 this species and the Mediterranean F. nubecula L. There is a 





