119 
minoribus cincta ; interstitiis longitudinaliter dense et undulatim 
striatis ; violacescenti-albida, ad umbonum regionem amethystina ; 
umbonibus acutis, subprominentibus, valde antrorsum inclinatis, in 
2 longitudinis collocatis ; margine ventrali medio subcurvato, 
postice subito subrecte, et antice subcurvatim, in utroque latere 
valde adscendente ; margine dorsali antico brevissimo, concavo, 
postico subhorizontali, vir curvato, infra angulo obtuso formante ; 
lunula ovali, lateraliter compressa, medio acute elevata, lamellis 
curvatis obtecta, alba, linea argutissima circumscripta; area 
lanceolata, ad basin lineis impressissimis constricta, medio in ale 
formam surrecta, lamellosa, area secunda lineari, ligamento im- 
merso, sub labiis hiantibus conspicuo ; intus amethystina, disco et 
impressionibus muscularibus pallidioribus ; sinu palliari magno, 
triangulari, apice late rotundato ; dente laterali crassissimo, 
papilliformi. 
Long. 30, alt. 28, crass. 14 mill. 
Hab. Australia. 
A very peculiar shell, differing from all its congeners. The out- 
line is that of D. pubescens, Phil. (celata? Reeve), and the wing- 
like elevation of the ligament-area is also similarly formed; but in 
other respects there exists no relation between these species. The 
amethystine colour is dark near the umbones ; towards the basal mar- 
gin it becomes lighter, and changes at last into a pale bluish white. 
The concentric strize are small and thread-like, moderately elevated, 
running almost equidistant from each other, and converging at the 
sides. The greatest peculiarity consists in the close undulated striee 
going from the apex to the base, but only in the interstices, which 
are thrice as broad as the concentric elevated lines. The white 
wing-like ligament-area and the white lunula, laterally compressed, 
and therefore shaped like the former, and both elevated on an ame- 
thystine ground, produce a very agreeable aspect. It is a charac- 
teristic sign of Dosinia that the lateral tooth of the hinge is very 
small, shaped like a wart, and very near the cardinal-teeth ; in this 
example the lateral tooth is as large and broad as in any known 
species. 
4. Dostn1a ovatus, Romer. D. testa rotundato-ovali, solida, 
tumidiuscula, posterius obtusissime angulata, valde inequilaterali, 
liris transversis densis, sublatis, rotundatis, ad latera, precipue 
postice, subundulatis, vix elevatioribus cincta ; pallidissime ferru- 
gineo-alba ; umbonibus acutis, vix prominulis, mediocriter reflexis, 
in + longitudinis positis; margine dorsali postico prelongo, 
arcuato, declivi, antico concavo, brevi, margine ventrali fere 
semicirculari, in utraque extremitate rotundatim et equaliter ad- 
scendente ; lunula cordata, convexiuscula, maxime impressa, argu- 
tissime circumscripta, longitudinaliter striata ; area lanceolata, 
concaviuscula, striata, ligamento subimmerso, conspicuo ; pagina 
interna ferrugineo-alba, fere omnino opaca; sinu palliari magno, 
angustissime triangulari, valde adscendente, apice obtusiusculo, 
lineis subrectis incluso; dente lunulari crasso, lateraliter com- 
