DIPLOMPHALUS. 113 



Genus GUESTIERIA, Crosse, 1872. 



G. POWISIANA, Pfr. PL 26, figs. 16-18. 



Shell very thin, polished, stimulate ; corneous, brown-raj'ed. 



Diam., 18 mill. 



Marmato, New Granada. 



Genus DIPLOMPHALUS, Crosse and Fischer, 1872. 



There is a certain superficial resemblance between this group 

 and Polygyra, Say the latter being Floridian,and belonging to 

 the true Helicidae. 



D. MONTROUZIERI, Souverbie. PI. 25, fig. 90. 



Shell thin, subdiaphanous, light corneous, very minutely 

 obliquely undulately striate ; spire depressed, deeply immersed 

 in the middle, suture plicately carinate. Diam. 8, alt. 4 mill. 



New Caledonia. 

 D. CABRITI, Gassies. PI. 25, figs. 91, 92. 



Rather thin, scarcely shining, with flexuous suboblique striae ; 

 corneous, crossed by reddish chestnut maculations ; centre of 

 spire profoundly immersed, suture crenulately carinate, mar- 

 ginate, last whorl carinate above and below. 



Diam. 8, alt. 4 mill. 



New Caledonia. 



First published as Helix volutella, a name preoccupied by 

 Pfeiffer. 



D. VAYSSETI, Marie. PI. 25, figs. 1-3. 



Rather thin, with suboblique, regular, flexuous impressed 

 striae ; corneous, with reddish chestnut maculations ; suture 

 crenulatety carinate, last whorl carinate above and below, and 

 marbled or strigate on the somewhat convex side with chestnut- 

 red. Diam. 6'5. alt. 2'5 mill. 



New Caledonia. 

 D. MARIEI, Crosse. PI. 25, figs. 6, 7, 10. 



Rather thin, somewhat shining, with impressed flexuous sub- 

 oblique striae ; corneous, maculated with reddish chestnut ; 

 suture submarginate, last whorl angulated above and below, 

 8 



