10 MOLLUSCA. 
Virrina RoBusTA (Gould). 
Testa helicoidea, transversa, depresso-globosa, sub-valida, polita, perlu- 
cida, dilute flavo-viridis, lineis incrementalibus regularibus, obtusis 
striata: spira obtusa, anfractibus tribus, ultimo magno ; apice sub- 
centrali ; subtus rotundata: apertura circularis ; margine sinistro 
superneé reflexo, rimam umbilicalem parvam formante. 
Sue. large, heliciform, depressed, firm, smooth, and diaphanous, 
faintly marked by somewhat regular lines of growth, and of a pale 
yellowish-green colour. Whorls three, forming an obtuse, depressed 
spire, the outer one rapidly increasing, rounded at periphery; suture 
rather deeply impressed or channelled. Beneath convexly rounded. 
Aperture transverse, ample, nearly circular, and largely modified by 
the penultimate whorl; lip slightly reflexed, forming a slight chink 
behind the columellar portion. 
Diameter half an inch; axis one-fourth of an inch. 
Inhabits New South Wales, and was presented by Mrs. Mitchell. 
This has about the size and form of V. nigra, Quoy, and is almost 
exactly like V. Freycinet7, Férussac. It is more globose and brilliant 
than V. marcida, and seems to be more substantially constructed than 
any other species. 
Figure 11, front; 11 @, back; 11 4, base of the shell. 
VITRINA CAPERATA (Gould ). 
Testa helicoidea, depresso-globosa, ad peripheriam obtuse angulata, 
tenuis, sub-opaca, striis incrementalibus conspicuis et rugis obliquis 
ramulosis, precipue supernis, exarata, dilute fulvo-cornea, arcte per- 
forata: spira anfractibus tribus cum dimidio convexis, citd crescen- 
tibus ; sutura profunda; apice subcentrali : apertura sub-circularis ; 
labro simplici, ad umbilicum everso; columella, callum simulante, 
secundem spiram tntroeunte. 
