128 AMERICAN JOURNAL 



LlTTORINA Newcombii, Rve. 



1857. Conch. Icon., Sp. 28. 



" Littorina ambigua, Rve., Sp. 64. 



This species varies widely in color and shape. Mr. Reeve has 

 described a dark, immature specimen as ambigua. 



Fossar Garrettii, Pease. 



1857. Adeorbis costata, Garr., Proc. Cal. Acad., p. 103. 

 Name preoccupied ; changed as above. 



RlSSOINA AMBIGUA, Gld. 



1849. Rissoa ambigua, Gld., Proc. Bost. Soc, p. 118. 



1852. " " " Am. Ex. Ex., p. 217, fig. 261. 

 1857. " multicostata, Garr., Proc. Cal. Acad., p. 103. 



RlSSOINA TRIDENTATA, Mich. 



1832. Desc. du genre Rissoa, p. 6, fig. 5, 6. 

 " Rissoa curta, Sow. 



1857. " crassilabrum, Garr., Proc. Cal. Acad., p. 102. 



Modulus tectum, Chem. 



1781. Troclms tectum, Chem., Con. Cab., vol. 5, pi. 145, fig. 



1567—68. 

 1791. Troclms tectum, Gme., Sys. Nat., p. 3569. 

 1797. Monodonta retusa, Enc. Meth., pi. 447, fig. 4. 

 1849. Modulus cidaris, Rve., Elem. of Conch., pi, 13, fig. 63. 



1853. " candidus, Petit, Journ. de Conch., p. 136, pi. 5, 

 fig. 11 



The characters on which M. Petit separates candidus are not 

 constant. 31. tectum occurs at the Hawaiian Islands and other 

 localities pure white, the umbilical fissure becomes closed and 

 smoothly covered with callus, and the whorls are sometimes 

 loosely convolute. 



Calyptrea cicatricosa, Rve. 



1858. Conch. Icon., Sp. 3. 



" C. saccliari-meta, Rve., Conch. Icon., Sp. 15. 



The latter is an immature shell. 



Nerita picea, Reel. 



1841. Rev. Zool. Soc. Cuv., p. 151. 



1852. Voy. Bonite, pi. 34, fig. 8—11. 



1855. Neritina insculpta, Rve., Conch. Icon., Sp. 70. 



