Shell minute, pale buff, with a brown Sinusigera nucleus of three and four subsequent well rounded whorls; suture appressed with a line thread in front of it; anal sulcus wide and shallow, leaving a wide fasciole, arcuately striated behind it; in front of the fasciole there is an obscure shoulder to the whorl; axial sculpture of incremental lines, most conspicuous on the fasciole, and a double row of obscure undulations at the periphery, most marked on the earlier whorls; spiral sculpture of 10 or 12 equal, small threads in front of the periphery with narrow interspaces; base evenly rounded, canal short, wide; the pillar straight, attenuated in front; aperture ovate, the outer lip thin, arcuate. Length, 4; diameter 1.5 mm. U. S. Nat. Mus. Cat. No. 108302.
One specimen off Georgia.
A variety from the same locality has the peripheral undulations absent and evenly rounded and spirally sculptured whorls, giving somewhat the aspect of an Astyris.

Remarks. P. bureaui resembles P. perpauxilla (Watson) from the West Indies but that species has a protoconch with coarser sculpture, and the adult whorls increase less rapidly. It also resembles P. anceyi, P. sandersoni and P. benedicti, from which species it can be separated in the following way:
P. anceyi has no axial ribs, except very thin and sharp ones, while bureaui has strong ones.
P. sandersoni has a bigger larval shell and thin, sharp, rather closely set axial lines resembling those of Drilliola which are lacking in bureaui.
P. benedicti has more evenly rounded whorls.
P. bureaui has a rather small, (diam. c. 600 µm) and slender larval shell. The general shape of the shell is rather conical. The axial sculpture is similar to that of benedicti; the spiral sculpture consists of two axial ribs on the upper whorls; on the later whorls, there is one more above, one between and one below these two.
P. obesa has a rather small (diam. c. 600 µm) larval shell with rather convex whorls. The shell is rather obese and the whorls very convex. The sculpture consists of poorly developed axial ribs and 3-4 spiral ribs with a smaller one between each of these.