We introduce this common shell for the purpose of pointing out those characters which induce us to consider it more as a distinct species than as a variety of _S. Luhuanus_ of authors; and this consists not so much in the colour of the inner lip, as in the almost total absence of that important part, which this shell invariably exhibits through all its growths: it is therefore, I think, contradictory to the meaning of the word to term that variable which is found to be constant, particularly where the point of distinction rests on a marked difference of _formation_ no less than of colour, though both shells are common to the Oriental seas. Minor differences exist, in the mouth of this always being pink, the inner lip white, and the outer lip but slightly lobed (or cut out) above: in _S. Luhuanus_ the mouth is deep scarlet, inner lip black and highly polished, and the outer lip deeply notched above; the two former characters, indeed, begin to show themselves at a very early growth of the shell. * * * * * STROMBUS Persicus. _Persian Strombus__--middle figures._ _S. testa sub-coniformi, brevi; spira conica, aequali; labio exteriore prominente, supra sinuato, intus glabro; interiore polito, albo._ Shell somewhat coniform, short; spire conic, equal. Outer lip prominent, sinuated above, smooth within; inner lip polished, white. * * * * * Allied, but sufficiently distinct from the last; the mouth is always smooth and white. It is a local species: a few received from the Persian Gulf are all I have yet seen, some were young, but no other variation was observable. * * * * * Pl. 54 [Illustration] MITRA lyraeformis. _Harp Mitre._ * * * * * GENERIC CHARACTER.--See Pl. 23. * * * * * SPECIFIC CHARACTER. _M. testa costis regularibus, carinatis, approximatibus: columella striata, juxta basin triplicata: spira subattenuata; apice subpapillosa._ Shell with regular, carinated, approximating, longitudinal ribs. Pillar striated, three-plaited near the base. Spire somewhat attenuated. Apex slightly papillary. * * * * *