GASTEROPODA. 59 
at tip. Whorls rounded, periphery scarcely angular ; beneath rounded. 
Aperture slightly transverse, rounded, or a little angular at the place 
of the keel. Umbilicus broad and deep, displaying all the whorls. 
Somewhat like H. rufa, Less. 
Diameter eight-tenths of an inch; axis seven-twentieths of an inch. 
Inhabits Upolu. Couthouy. 
b. Of the same form, but of a honey-yellow colour, with a single 
very narrow brown band revolving upon the spire, and another be- 
neath, near the keel. 
Diameter three-fourths of an inch; axis three-tenths of an inch. 
Inhabits Upolu. Couthouy. 
c. More depressed, of a lenticular form, acute-angled at periphery, 
the whorls scarcely convex, each one having above a rusty brown 
band, and another of yellowish, about equal in width, somewhat blend- 
ing with each other; beneath flattened, rusty-brown; aperture trans- 
verse, triangular; umbilicus large. 
Diameter seven-tenths of an inch; axis one-fourth of an inch. 
Found by Mr. Couthouy, at the roots of trees, in moist places ;— 
Eimeo and Upolu. The animal has a dull fawn colour. 
d. Somewhat more conical, with a more flattened base, thinner and 
more delicate, very acute at periphery, of a delicate pale green colour, 
having a single thread of brown revolving on the spire, and a broader 
one underneath ; umbilicus broad; aperture acutely angular. 
Diameter thirteen-twentieths of an inch; axis eleven-fortieths of an 
inch. 
Inhabits Tongataboo. 
It is hike H. planorboides, Lesson (H. solarium, Quoy). It is, how- 
ever, smaller, and more broadly umbilicated. 
e. Low pyramidal, flat underneath, having a very acute, compressed 
keel at the periphery : the whorls are somewhat excavated, of a bright 
leaf-green colour, with a brownish band at each edge of the whorls 
above, and a whitish sutural line; umbilicus much smaller than in 
the other varieties; aperture very acutely triangular. 
Diameter thirteen-twentieths of an inch; axis three-tenths of an 
inch. 
