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15 
aperture is parallel to the axis, ear-shaped, with a broadly expanded 
white peristome, whose right margin is produced and forms a rounded 
angle; the aperture is furnished within with six lamellar teeth, two 
on the columellar side, of which the posterior is compound, three 
within the basal margin; and a single compound plate which is fur- 
cate posteriorly and bipartite anteriorly within the right hand margin. 
In Mr. Cuming’s collection. 
From Pernambuco. 
2. DESCRIPTION OF TWO NEWLY DISCOVERED SPECIES OF 
Cycutostoma. By-G. B. Sowrersy, F.L.S. 
(Mollusca, Pl. II. figs. 4, 5, 8, 9.) 
1. CycLostoma rormosuM. Cycl. testd suborbiculari, subdepres- 
sd, tenuiusculd, spiraliter striatd, tricarinatd, fulvo-rufescente ; 
spird brevi, acuminatd, anfractibus quinis rapide crescentibus, 
rotundatis, carinis duabus validis, albicantibus castaneo-artt- 
culatis ; anticée striis subobsoletis, gradatim majusculis, cari- 
ndque tertid umbilicum circumferente; suturd validd, levi; 
aperturd magnd, feré circulari, postice paululim acuminatd, 
peritremate latiusculo reflexo, incisuris parvis tribus, ad carinas 
externas idoneis ; umbilico magno, profundo, spiraliter striato, 
striis exterioribus gradatim mapusculis. 
This very handsome Cyclostoma bears a general resemblance to 
C. Cuvierianum, though easily distinguishable by having three distinct 
keels, by having a more acuminated apex, and by the latter having 
the spiral strize decussated by other sharp strie parallel with the 
lines of growth. The C. formosum is nearly orbicular, though some- 
what depressed ; it is rather thin and smooth, and of a reddish fulvous 
or brown colour : its spire is rather short, but acuminated, consisting 
of five volutions which are of a roundish form and increase rapidly, 
and are ornamented with two keels which are of a pale colour, spotted 
with chestnut brown: anteriorly the striz are rather indistinct, but 
larger; and there is a thick keel surrounding the umbilicus; the 
suture is distinct and smooth, but belted posteriorly by the middle 
keel ; the aperture is large, nearly circular, slightly acuminated poste- 
riorly, with a rather broad reflected peritreme, in which are three 
little cuts answering to the ends of the external keels; the umbilicus 
is large and deep, spirally striated within; the outer striz being the 
larger. 
ted Madagascar, in the collections of A. L. Gubba, Esq., Havre, 
and Mr. Cuming. 
2. CycLosToMA APLUSTRE. Cyel. testd suborbiculari, tenuius- 
culd, levi, albicante, fasciis nonnullis posticis, angustis, castaneis, 
subinterruptis, striisque tenuissimis spiralibus, ornatd ; spird le- 
vatiusculd, subacuminatd, apice obtuso; anfractibus quinis rotun- 
datis, creberrimé transversim striatis, striis posticis fortioribus, 
anticis fere obsoletis ; umbilico magno, intus spiraliter striato, 
striis tenuissimis; aperturd feré circulari, posticé paululim 
