GASTEROPODA. 49 
Diameter one-eighth of an inch; axis one-sixteenth of an inch. 
Inhabits Maui, Sandwich Islands. Drayton. 
This little pellucid shell, though imperfect, is so well marked by 
its compressed, lenticular form, sharp carination, and numerous 
whorls, that I venture to pronounce it a new species. 
Figures 62, 62a, 626, three views of the shell, magnified; 62c, 
natural size. 
HELIx GrapatTa (Gould). 
Testa parva, planorboidea, tenuis, nitida, rufo-viridis, luteo radiatim 
variegata, supra depressa, infra acetabuliformis: spira anfractibus 
quinque convexis, intra umbilicum angulatis, oblique et confertim 
striatis et cum strus interruptis volventibus decussatis ; ultimo suban- 
gulato, versus aperturam deflexo ; sutura canaliculata: apertura ob- 
liqua, subcircularcs ; labro acuto, ad umbilicum reflexo. 
Helix gradata, Goutp; Proceed. Boston Soc. Nat. Hist., u. 172. 
Sept. 1846. Expedition Shells, 21. Preirrer; Monog. Helic. Viv., 
1. 104. 
SHELL planorboid, convex above, cup-shaped beneath, thin, shining, 
with coarse, regular, and crowded striz, crossed by interrupted, equi- 
distant revolving lines. Whorls five, separated by a deeply chan- 
nelled suture, the outer whorl a little angular at periphery ; beneath 
sharply angular as it borders the broad umbilicus, and so are each 
and all the whorls as they present their edge in the vortex: aperture 
circular or a little transverse, slightly modified by the last whorl: lip 
simple, somewhat everted at the umbilicus. Colour brandy-red, some- 
what rayed by unequal and irregular stripes of pale yellow. 
Diameter half an inch ; axis one-fifth of an inch. 
Found at the Tonga Islands. 
It has the shape and size of H. striatella, Anthony, but the umbi- 
13 
