TERRESTRIAL MOLLUSCA INHABITING SOCIETY ISLANDS. 71 
reef. It is no less singular to note its absence from Huaheine and Moorea, though at 
the former island we find the closely allied P. annectens. 
Its most essential characters are its graceful oblong-conic shape, narrow body-whorl, 
uniform whitish horn-color and broadly expanded white lip. 
Reeve has erroneously described and figured this species under the name of P. 
“«Oarteretensis.” Quoy and Gaimard. ‘The latter author’s P. Carteriensis (IT liz) is of 
an entirely different type. 
P. rusca, Pease. Plate III, fig. 50. 
Partula fusca, Pease, Amer. Jour. Conch., 1866, p. 193; Proc. Zool. Soe., 1871, p. 473 
Paetel, Cat. Conch., p. 104. Binney, Proc. Acad. Nat. Sci. Phil., 1875, pp. 245, 247, 
Plate XIX, fig. 9 (anatomy). Pfeiffer, Mon. Hel., viii, p. 205. Schmeltz, Cat. Mus. 
Godeff., vi, p. 81. Hartman, Cat. Part., p. 6; Obs. Gen. Part., Bul. Mus. Com. Zool., ix. 
p. 182 (excl. ovalis and lugubris). 
Partula protea, Pease, MS. Coll. Pease, 1863. Schmeltz, Cat. Mus. Godeff., v, p. 92. 
Pfeiffer, Mon. Hel., viii, p. 209. 
Partula faba, var., Carpenter, Proc. Zool. Soc., 1864, p. 675 ( = protea). 
Partula navigatoria, Carpenter, |. c., not of Pfeiffer. 
The metropolis of this very variable ground species is in Vaioara valley, on the 
west coast of Raiatea, the headquarters of P. Garrettii and navigatoria. It has not 
migrated any to the southward, but to the northward it occurs sparingly far up in 
Huaru valley. On the opposite side of the island it is found in Tepua valley, and I 
took a few in a small ravine more to the southward. The Tepua shell, which is the 
protea, Pse., differs none from his fusca. 
Hybrids between protea and the arboreal P. faba are not uncommon, and are 
usually found adhering to the lower parts of the trunks of trees. 
In Vaioara, hybrids between fusca and navigatoria, and between the two former 
and faba, are so frequent as to be very embarrassing in the separation of the three 
species collected in that valley. Like the Tepua hybrids, all those between the two 
ground species and the arboreal faba live on the lower parts of the trunks of trees. 
P. fusca may be described as follows :— 
Shell umbilicated, solid, varying from an abbreviate-ovate to oblong-ovate, roughly 
striated by irregular lines of growth, and the usual fine spiral incised lines become 
evanescent on the body-whorl; spire convexly conical, less than half the length of the 
shell; suture linearly impressed, frequently margined by a thread-like white line; 
whorls 5-6, more or less flatly convex, last one large, convex, rounded or turgid, some- 
times slightly angled just above the aperture ; base more openly umbilicated than usual 
in the ground species; aperture subvertical, oblong, sides nearly parallel ; parietal 
region more or less glazed with callus, and sometimes dentate ; peristome rather broadly 
expanded, moderately thick, slanting, flat or concave, strongly incrassated within and 
sinuous above; columellar lip depressed, receding or transversely grooved above. 
Color very variable : whitish’ corneous, straw-yellow, fulvous, light or dark chestnut, 
