57 
Rissoina d’Orbigny. 
. albida Ad. station: —? —; habitat: St. Thomas; 
A. H. Riise! 
. Browniana d@Orb. station: In sand on the beach; 
habitat: St. Thomas; Haity; Martinique; de Candé! 
St. Thomas & St. Johns; Krebs! remark: described in 
»Mollusques de Cuba‘ 2 part, page 28. 
. eancellata Ph. station: dead in the sand on the 
beach; habitat: Cuba; Pfeiffer! remark: described in 
Zeitschrift 1847 page 127. 
. Catesbya dOrb. station: dead in the white sand on 
the beach and life on dead madrepores laying on the 
beach between high and low water mark; habitat: 
Cuba; Sagra! St. Thomas; R. Swift! Martinique; St. 
Thomas; Haity; Candé! Portoplata; St. Thomas; St. 
Croix; St. Johns; St. Martin; Krebs! Guadeloupe; Beau! 
St. Thomas; A. H. Riise! remark: This R. Cat. dOrb. 
is certainly the same as the shell A. H. Riise Esq. has 
in his Collection by the name of Rissoa Dunkeri Pf. and 
we consider it the same shell as C. B. Adams Rissoa 
scalaroides, R. scalaroides minor and R. scalarella. The 
number of ribs and their proportion are very variable ; 
we have a large number of specimens before us and we 
have come to the conclusion that they are one species. 
. decussata Montg. station: — ? — ; habitat: St. 
Thomas; A. H. Riise! 
. dubiosa C. B. Ad. station: —? —; habitat: St. 
Thomas; A. H. Riise! 
. elegantissima dOrb. station: only found dead in 
the sand on the beach; habitat: Haity; dOrbig.! St. 
Martin; Anguilla; Krebs! remark: Described in ,Mol- 
lusques de Cuba“ part 2, page 26. 
