418 FUNAFUTI ATOLL. 
Rissoa INVISIBILIS, Sp. NOV. 
(Fig. 9). 
Shell small,sturdy, ~ 
conic ovate. Colour 
white. Whorls four. 
Sculpture — distant, 
longitudinal, sharp 
costze are crossed by 
three similar spiral 
ribs, which together 
divide the surface 
into nearly square 
compartments ; at 
the intersections are 
small projections. 
One spiral ridge 
alone appears on the 
Fig. 9. penultimate whorl, 
both it and the longitudinals vanish on the whorl above. The 
base is flattened, umbilicus narrow and deep. Aperture round, 
columella slightly sinuate, recurved over the umbilicus, lip with 
a heavy varix. Length 1:15, breadth -63 mm. 
One specimen from the sand of the lagoon shore. 
Shape and sculpture ally this to the group including R. trajectus, 
Watson. The heavy lip, open pattern of ornament, and com- 
parative breadth of the shell clearly distinguish the novelty, one 
of the smallest of the genus, from any known form. 
RIssOINA EXASPERATA, Sowverbie. 
(Fig. 10). 
Souverbie, Journ. de Conch., xiv., 1866, p. 259, pl. 
ix., fig. 110. 
To this species is referred with doubt a series from 
Funafuti. The published account is insufficient for 
accurate determination, and my principal reason for 
considering the Ellice shell to be 2. exasperata is its 
identity with a common New Caledonian shell 
which I have myself collected at Panie, N.C., and 
have received from Noumea, from Mr. R. C. 
Rossiter. That Conchologist regards it as A. ex- 
asperata, and it answers fairly to Souverbie’s 
description as far as that goes, but it is less easy to reconcile it 
with his figure. 
This figure, perhaps drawn from a worn specimen, was so badly 
copied by Weinkauff* as to almost eliminate the name character 
and represents a smooth ewasperata. Tryon unfortunately appears 
* Conchylien Cabinet, i., 22, 1885, p. 54, pl. xiv., fig. 10. 
