On Two new Species of Mollusca. 491 
LVU.—Deseriptions of Two new Mollusca of the Genera 
Leptothyra and Mitra. By G. B. Sowersy, F.L.S. 
Leptothyra fultoni, Sowerby, sp. n. 
Testa minuta, umbilicata, globosa, solidiuscula, rotundata, spiraliter 
anguste costata, lineis spiralibus nigro-fuscis interruptis ornata ; 
spira brevis, apice obtusa; anfractus 4, convexi, rotundati, 
sutura impressa sejuncti ; anfractus ultimus globosus, dextrorsum 
leviter obliquus, in regione umbilicalis albo callosus; umbilicus 
parvus, profundus, circularis ; apertura leviter obliqua, rotundata, 
intus margaritacea ; peristoma acutum, columella vix incrassata. 
Operculum calcareum, album, tenue, planum, leve. 
Lat. 23, alt. 22 mm. 
Hab. Aden. 
This pretty little shell is chiefly distinguished by its dark 
brown interrupted spiral lines and narrow spiral ridges. 
Compared with the New Caledonian Turbo latus (Montr.) 
it is much smaller and rather less solid ; its spiral ridges are 
less numerous and narrower. 
c 
Leptothyra fultoni, Sowerby, sp. n. 
Mitra fidis, Sowerby, sp. n. 
Testa subovata, solidiuscula, ventricosa, pallide cinnamomea, griseo- 
fusco variegata, glabra, longitudinaliter lirata; spira acuta, 
mediocriter elata; anfractus 6, levissime convexi, sutura anguste 
canaliculata sejuncti; anfractus ultimus $ longitudinis teste 
gequans, convexus, infra attenuatus, haud striatus; apertura 
latiuscula, intus levis, griseo-fusca; peristoma acutum, leve, 
leviter incrassatum, arcuatum, postice anguste sinuatum; colu- 
mella leviter callosa, fusca, quadriplicata, plicis crassiusculis, 
leviter obliquis ; canalis brevis. 
Long. 14, lat. 7; apert. long. 9, lat. 3 mm. 
Hab. South Africa. 
This shell is in form very like I. patula, Reeve, from 
which it is distinguished by having numerous prominent 
longitudinal folds or lire, which are smooth, rounded, and 
very slightly arcuate. Having seen a considerable number 
