216 MELANIIDiE. 



vdr. 

 1 Brazil ; ex c. Prof. W. Newcomb . 

 Resembles M. Brot's pi. 39, fig. 12 c. 



Genus DORYSSA, H. Sr A. Adams. 

 Gen. Moll. I, p. 304, 1856, type M. atra, Richard, 



1. Doryssa transversa [?]. 



Melania transversa, Lea, Zool. 1850, Guiana. 



var. subdevians, nov. [? D. subdevians, n. sp.]. 

 3 Amazons; ex c. Prof. W. Newcomb [labelled " Mel. transversa, Rv."^. 

 Long. 26, diam. 12| mil. 



Strongly decollate, three or four whorls only remaining. 

 Dark-brown colour, not light as M. Brot says Reeve's species 

 always is. Longitudinal sculpture obsolete on the last whorl. 

 But for its much larger size, M. Brot's pi. 35, fig. 10 A. [D. 

 devians'] well represents the form. 



2. Doryssa consolidata. 



Bulimus consolidatus, Bruguiere, JEne. Meth., 1790 ; fide JBrot=n. decollata, 

 Gmelin^Mel. circumsulcata, BuscJi, 1858 = Mel. scarabus, Reeve. 



3 "To cantines River," Brazil; ex e. Prof. W. Newcomb [labelled " Mel. 

 scarabus, Rv."2- 



Last whorl less convex than in M. Brot's figure ; it is also less 

 decollate, four whorls remaining. 



3. Doryssa aquatilis. 



Melania aquatilis. Reeve, Icon., 1859, Rio Branca, Guiana ; fide Reeve 

 \m '* errata"'} and Brot =Mel. branca, Rv., 1860, from Rio Branca. 



1 South America ; ex c. G. Nevill, Esq. 



4. Doryssa subimbricata. 



M elania subimbricata, Fhilippi, Abb. Ill, 1851, Eab. ? [not Faunus subim^ 

 bncatus of Br of]. 

 5 Brazil; ex c. Prof. W. Newcomb [labelled "M. subimbricata, Ph."], 



