14 NON-MARINE MOLLUSCS OF SURINAM. 
Post Groningen. van Heurn, 1911. 
Only a single specimen of this very fragile shell, agreeing 
with the cited deseription and figure. 
» 929. DRYMAEUS DEBILIS Beck. 
Bulimulus debilis, Beck, Index Moll., 1837, p. 65. 
Drymaeus debilis Beck, Pilsbry, Man. of Conch., 2. ser., Vol. 
XI, 1898, p. 314, Pl. 26, f. 74, 75. 
Albers, 1860, p. 216. Surinam. 
Martens, 1873, pp. 186, 215. Surinam. 
von Martens says that the specimen in Albers’ collection, 
labelled , Dutch Guyana’, is an immature one, which is much 
more agreeing with shells, he took for D. membranaceus 
Phil. (see next species). 
? 30. DRYMAEUS VENEZUELENSIS Marts. 
Otostomus membranaceus, Martens (non Phil.), Festschr. hun- 
dertj. Best. Ges. naturf. Fr. Berlin, 1873, p. 186 (pr. p.). 
Otostomus venezuelensis, Martens, Biol. Centr.-Amer., moll. 
terr., 1893, p. 224. 
Drymaeus venezuelensis Marts., Pilsbry, Man. of Conch., 2. 
ser., Vol. XI, 1898. p. 312, Pl. 50, f. 80. 
Martens, 1873, pp. 186, 215. Surinam. 
The locality ,Surinam” in von Martens’ list apparently is 
based, for this species as well as for the preceding, on 
one and the same specimen in Albers’ collection. There 
being much confusion as to the identification of von Martens’ 
specimens of D. membranaceus (see Pilsbry, Vol. XI, p. 238 
and Vol. XII, p. 74), and moreover the single specimen 
from Surinam of Albers’ collection, according to von Martens, 
being immature, it is preferable to cancel in von Martens’ list 
D. debilis and D. membranaceus, and in stead of both spe- 
cies, to mention only a Drymaeus spec. as occurring in 
Surinam. 
31. DRYMAEUS ZIEGLERI Pfr. 
Bulimulus ziegleri, Pfeiffer, Proc. Zool. Soc., 1846, p. 113. 
Drymaeus ziegleri Pfr., Pilsbry, Man. of Conch., 2. ser. Vol. 
XII, 1899, p. 39, Pl. 40, f. 4—6. 
Notes from the Leyden Museum, Vol. XXXVI. 
