Mollusca of Dominica. | 433 
13. Succinea approximans, Shuttl. 
14. Cyclotus amethystinus, n. sp. 
Testa turbinato-depressa, rubra vel straminea, subdiaphana, spira- 
liter striata, lines incrementi rugose ; spira depressa, conoidea ; 
anfr. 5, convexi, infra leves, supra (in forma «) spiraliter lirati 
lineis angustioribus quam interstitia eorum (in forma £6 leves) ; 
umbilicus latus, profundus; apertura parum obliqua; peristoma 
simplex, continuum, breviter affixum, margine externo parum 
prominente. 
Alt. 83 millim., lat. maj. 19, lat. min. 15. 
Operculum corneum, diaphanum, externe concavum, interne carti- 
lagineum. | 
_ @. Shell turbinate-depressed, reddish or straw-coloured, sub- 
diaphanous, spirally striate, the strie of growth generally 
rather rugose; spire depressed, conoidal; whorls 5, convex, 
smooth beneath, lined above by spiral strie narrower than 
their interstices, the last scarcely descending anteriorly. Oper- 
culum horny, diaphanous, concave externally, cartilaginous 
within, the nucleus projecting internally; with from ten to 
fourteen very narrow whorls, their rather lamellar outer edges 
slightly free. 
8B. Smooth, shining, not striate spirally, generally some- 
what more depressed, deep chestnut or reddish brown ; whorls 
a little flattened near the suture. Operculum as in a, 
_ This is a notable species, owing to its operculum, which 
departs widely from that usual in this genus. In no specimen 
did it present the least approach to the shelly consistency of 
the opercula of most Cyclot’. ‘The spiral striation of the shell 
is generally very distinct, but in var. 8 it is altogether want- 
ing. ‘The present species approaches C. popayanus in shape, 
being, however, a little more depressed; and it is not closely 
allied. 
15. Helicina plicatula, Pfeiffer. 
Some examples of this species are reddish, and some are 
yellow. 
16. Helicina epistilia, n. sp. 
Testa orbiculato-conoidalis, solidiuscula, lineis incrementi striata, 
rubro-brunnea vel obscure flava; spira elevata, apex acuminatus; 
anfr. 5, paulum convexi, inferne applanati; sutura paululum 
crenulata, parum descendens; apertura parva, semiovalis, lata 
geque ac alta; peristoma anguste reflexum, parum incrassatum ; 
callus basalis tenuis, vix distinctus ; columella simplex. 
Alt. 53 millim., lat. 84. 
Operculum pallide corneum. 
_ An orbiculate-conoidal, obscurely yellowish or reddish shell, 
