LOBIGER. 169 
produced. Aperture semioval, obliquely truncated in front, sub- 
angulated behind; columellar lip thin, with a thin, narrow callus 
recurved over the spire; outer lip thin, arcuate and simple. 
Alt. 7, diam. 5 mill. Swimming lobes two, one anterior, the other 
posterior. (Fischer.) 
Guadeloupe, West Indies. 
L. sowerbii Fiscu., Journ. de ConchyL, v, 1856, p. 278, pl. 11, f. 
7-10.— L. sowerbyi Fisch., Morcu, Malak. BI., xxii, p.179. 
Differs from the other forms known in the single pleuropodial 
lobe on each side. 
Subgenus PreryGopuysis Fischer, 1885. 
Pterygoohysis FiscHEeR, Man. de Conch., p. 571. 
Four tentacles developed on head ; pleuropodial lobes four, very 
long, with scalloped edges. 
L. viripis Pease. PI. 10, figs. 37, 38. 
Shell ovate, rather thin, longitudinally striated, white, covered 
with a yellowish epidermis; left margin slightly dilated. Aperture 
oblong-oval, rounded in front, produced, contracted and subangulate 
behind. Spire involute, concealed ; lip slightly arcuate, its margin 
acute. (Pse.). 
Animal elongate; tail, margins of the foot and centre of natatory 
lobes papillose ; tail long, arched, gradually tapering to a rounded 
point. Tentacles four, auriform, subconvolute, somewhat dilated at 
the ends and truncate. Eyes immersed behind the posterior pair. 
Natatory appendages thin, elongate, anterior pair rather less than 
the whole length of the animal, posterior pair a little shorter than 
the anterior, widest at their outer halves, and their sides deeply in- 
cised, giving them a leaf-like appearance. Locomotive disk like 
Aplysia. Color pale pea-green, tips of the tentacles tinged with yel- 
low, a dusky marginal band along the edge of the body; the upper 
surfaces of the natatory lobes are greenish centrally, fading into 
yellowish pink towards the margins, which are white ; lower surface 
of same color, but brighter, and margins dusky. 
Tahiti (Mts.); Huahine, among sea-weed on sandy bottoms in 
sheltered places (Pse.). 
Heviger . . . .?-Prase, P. Z..5., 1861, p. 246; Lobiger 
viridis Pras, P. Z. S., 1863, p. 510.—L. picta Pse., Amer. Journ. 
