390 MANUAL OF THE MOLLUSCA. 
Synonyms, Nanina (citrina), Gray; Ariophanta (lavipes, 
Pl. XI1., Fig. 9), Desm. 
Shell thin, polished ; peristome thin, not reflected. 
Animal with the tail truncated and glandular, lke Aricn ; 
mantle-margin produced, partly covering the shell. 
Distribution, 295 species. South Asia and Islands, New Zea- 
land, Pacific Islands, West Indies. 
Tanystoma (tubiferum), Benson, 1856. Shell like Anastoma, 
minute, umbilicated; aperture disengaged, ire 
s5puined Banks of the Irawadi, above Prome. 
Pfeifferia (micans), Gray, is a Nanina without the mucus-pore 
at the tail. Philippines. 
Vitrina, Draparnaud. Glass-snail 
Type, V. Draparnaldi, Pl. XII., Fig. 28. 
Synonym, Helicolimax, Fer. 
Shell imperforate, very thin, depressed ; spire short, last whor 
large; aperture large, lunate or rounded, columellar margin 
slightly inflected, peristome often membranous. 
Animal elongated, too large for complete retraction into the 
shell; tail very short; mantle reflected over the shell-margin, 
and furnished with a posterior lobe on the right side. Lingual 
teeth (of type) 100 rows of 75 each; marginal teeth with a single 
long, recurved apex. (Thomson.) Occasionally animal-feeders, 
like the slugs. 
V. Cuvieri and Freycineti (Helicarion, Fer.), tail longer, more 
abruptly truncated, with a caudal gland like arion, mantle more 
developed. 
Distribution, 87 species. Most abundant in north part of the 
Old World. 
Sub-genera. Duudebardia, Hartm. (Helicophanta, Fér.) Y. 
brevipes, Pl. XII., Fig. 29. 
Shell perforated, horizontally involute; aperture oblique, 
ample. 8 species. Central Kurope. 
Simpulopsis (sulculosa), Beck. 
Shell succinea-shaped. 65 species. Brazil. 
SuccINnEA, Draparnaud, Amber-snail 
Type, 8. putris, Pl. XII, Fig. 23. 
Synonyms, Cochlohydra, Fér.; Helisiga (S. Helense), Less. ; 
Amphibulima (patula), Beck; Pelta (Cumingii), Beck. 
Shell imperforate, thin, ovate or oblong ; spire small ; aperture 
larve, obliquely oval; columella and peristomo simple, acute. 
Asim large, tentacles short and thick, foot broad; lingual 
