LIMNATID-E. 29 
Sub-Order—Basommatophora. 
Eyes sessile. Operculum absent, or present. Aquatic. 
FAMILY—LIMNAAIDA. 
Radula with numerous quadrate teeth, in transverse rows, the central 
minute, the laterals uncinated. Head with a broad short muzzle, 
dilated at the end; mouth with a horny upper jaw; tentacles 
flattened or filiform, with the eyes sessile at their inner bases. Mantle 
margin variously modified ; respiratory orifice at the right side. Foot 
flattened, lanceolate, or ovate. Excretory orifices on the left side of 
the neck. Shell varied, thin, horn-coloured ; no operculum. Animal 
fluviatile, living in the water, but coming to the surface to respire air. 
Sub-Family—A neyline. 
Shell non-spiral, limpet-like. 
Genus, LATIA—Gray. 
Shell semi-ovate, spiral of one or more rapidly enlarging whorls; spire 
short, posteriorly reclined ; basal margin with a thin, narrow, flat, hori- 
zontal lamina, occupying the hind half of the left side, the left hinder 
edge bent down, and produced into a broad expansion on the right side. 
Eyes on the outer bases of the tentacles. 
New Zealand only. 
L. neritoides, Gray, P.Z.S., 1849, p. 168; Reeve, Conch, Ic. f. 
34; Chenu fig. 3573. Pale brown, spirally striated, internal laminze 
white, transparent (Gray). Shell ovate, smooth, vertex rather swollen, 
produced, olive horny (Reeve.) 
Length, ‘25 inch. 
Auckland (Sinclair and Geenwood.) 
The vertex is said to be more swollen and produced in proportion 
to the size of the shell in this species than in the next. 
L. lateralis, Gould, U. S. Ex. Ep. xii., p. 153; Reeve, Conch, Ic., f. 
35. Shell somewhat squarely ovate, rather depressed, obscurely grooved 
at the side; greenish-horny (Reeve.) 
Length, *4 inch. 
Sub-Family— Limneine. 
Shell spiral, more or less elongated, the last whorl large; aperture 
oblong. 
Genus, PHYSA—Draparnaud. 
Tentacles slender, setaceous. Mantle covering part of the shell, 
the margin fringed or digitate. Foot long, acuminate behind. Shell 
sinistral, oblong, thin, polished ; spire acute ; aperture oval, rounded 
anteriorly, not dilated ; inner lip spread over the last whorl, simple in 
front ; outer lip acute. 
P. wilsoni, Zyvon, Am. Jour. of Conch. ii., p. 109, pl. 2, f. 17. 
E 
