In Latin (Smith): Testa parva, fusiformis, turrita, alba, epidermide tenui grísea induta : anfractus 11, superiores erosi, caeteri lente accrescentes, supra ad suturam carina tuberculata cincti, in medio angulati, serie nodulorum ornati, liris tenuibus spiralibus paucis lineisque incrementi flexuosis sculpt i, liris infra angulum minute nodulosis, anfractus ultimus intra peripheriam liris transversis 14-15, partim nodulosis, cinctus; apertura parva; labrum tenue, supra angulum haud profunde sinuatum, infra arcuatim prominens; columella subrecta, callo tenui induta ; canalis brevis. Longitudinem 18 mm., diam. 6 ; apertura cum canali 6 mm. longa, 2 ½ mm lata.

Shell small, 18 mm. in height, claviform, with tall spire, twice height of aperture plus canal, and truncated base. Whorls about 11, tip eroded; sculptured with flexuous thin axials, which thicken both at the periphery and at the suture. Axials crossed by spiral cords of about equal strength, except on the shoulder slope, where they are finer. Four closely spaced spiral threads in the interstices of (he peripheral nodes. Colour while, covered with a thin greyish periostracum.

This species resembles patruelis (Smith) in the latticed effect of the axial and spiral sculptural pattern, but the peripheral nodes are smooth elongated knobs, taller than wide, representing thickenings of the axials, which are more flexuous than in patruelis. The axials again thicken subsuturally, in the form of an irregularly gemmate fold.

The shell from stn 176 (JOHN MURRAY EXPEDITION) is quite typical. It consists of protoconch and 7 teleoconch whorls. The previously undescribed protoconch is basically similar to that of P. melvilli figured by Powell (1969, pl. 242, fig. 2). It consists of 2.5 whorls with smooth glossy surface, the tip is small and papillate, and a thin low-set keel is developed on the last whorl. There are 17 axial ribs on the body whorl and 15 on the penultimate one.
The shells from stn 180 were referred to P. agalma with some doubts. They differ in more numerous peripheral tubercles, weaker axial and spiral sculpture, and in the presence of two spiral threads on the subsutural fold and two riblets below the periphery on the spire whorls. They seem to be a transition to P. melvilli Powell, 1969 in sculpture, but that species is almost half the size, with a proportionally higher spire and truncated anterior end. However, the general pattern of sculpture, shell outline and the character of protoconch are similar in all JME shells and those from stn 180 are provisionally assigned to P. agalma pending examination of additional material.

Locality: Sri Lanka, west of Cape Comorin in 464 fathoms, green mud and sand.