216 MELANIIDJI. 



var. 

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

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



Genus DORYSSA, H. .y A. Adams. 

 Gen. Moll I, p. 304, 1S56, fi/pe M. atra, Richard. 



1. Doryssa transversa [?]. 

 Melaiiia trausversa, Lea, Zool. 1S50, Guiana. 



var. SUbdevianS, nov. [? D. subdeviaus, 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 eonsolidata. 



Biilinius consolidatus, Brugiiiere, Enc. Mefk., 1790 ; fide Brot=II. decollata, 

 Gmelin=Mel. cirewnsulcata, Busch, 1858= Mel. scarahus, Reeve. 



3 "Tocantines River," Brazil; ex c. Prof. W. Newcomb [labelled "Mel. 

 scarabus, Rv."'\. 



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 Reere 

 [in "errata"'] and Brot ^=Mel. branca, Rv., 1800, from Rio Branca. 



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



4. Doryssa subimbricata. 



Melania subimbricata, Philippi, Abb. Ill, 1851, Sab.? [not Faiinus subitn- 

 bricatus of Brot], 



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



