SUCCINEID. 87 
than a slug. No exact generic characters are given. O. Sys- 
mondwi, Gray. Gaboon, Africa. 
EUMELUS, DEROCERAS, ZILOTEA, URCINELLA, TESTACINA, LIMACIAS, 
Rafinesque. All unrecognized genera of slugs. 
PARMULA, SCUTELLIGERA — Larvee of insects —Gray, Cat. Brit. 
Mus., 161. 
+ + Elasmognatha. 
Jaw with a superior quadangular accessory plate. 
Famity SUCCINEID &. 
Shell oblique, sometimes flattened, paucispiral, very thin, 
transparent. = — 
Inferior tentacles but slightly developed or wanting ; jaw with 
a median quadrangular accessory piece, projecting upwards 
(xiii, 63) ; central tooth tricuspid, same size as the laterals which 
are bi- or tricuspid, marginals narrow at base, multicuspid. 
SuccingeA, Drap., 1801. 
Syn.—Cochlohydra, Fer., 1819. Neritostoma, Klein, 1753. Lu- 
cena, Oken, 1815. Amphibina and Amphibulina, Hartmann, 1821. 
Distr.—200 sp., world-wide; subaquatic, living in damp places, 
near the margins of streams. Fossil; Hocene—. 
Shell oval, very fragile and transparent; spire short; the 
whorls few, and very rapidly enlarging ; aperture oval; outer lip 
thin, not reflected, united below by a broad curve with the thin, 
smooth columella. 
Animal large, usually barely retractible within its shell; ten- 
tacles short and thick, the inferior pair inconspicuous; foot broad, 
TAPADA, Studer, 1830. (Succinea, restricted.) Whorls well- 
rounded, with impressed sutures. §S. obliqua, Say (c, 32). U.S. 
BRACHYspPIRA, Pfr., 1855. Shell ovate, inflated; spire very 
short, acuminate; last whorl flattened, scutiform; aperture 
large, angulated. S. ovalis, Gould. SS. putris, Linn. (c, 33). 
TRUELLA, Pease, 1871. Shell elongate, slender; aperture con- 
tracted behind. 3sp. Polynesia. §S. procera, Gld., ete. 
PELTA, Beck,1837. S. Cumingii, Beck. Ins. Juan Fernandez. 
HELISIGA, Lesson, 1829. Shell ovate-ventricose; spire very 
short; aperture wide, patulous; peristome acute. Eye-peduncles 
short, cylindrical, swollen at the base; tentacles short, rudi- 
mentary. S. Sancta-Helenx, Lesson. St. Helena. 
Omatonyx, d’Orb., 1841. 
Distr.—5 sp. West Indies and Brazil. O.. unguis, d’Orb. 
(c, 36). 
