Coæ not so deep as their respective segments. Fourth segment of pleon produced into two acute spines on its postero-dorsal margin, and having its postero-inferior angles also acutely pointed. Eyes oblong, black. Superior antenna as long as the body; peduncle having its first joint as long as the second, but twice as broad, third short; secondary appendage shorter than last joint of peduncle, about 6-jointed; flagellum subequal with peduncle, very many-jointed (about 50–60), joints at first more than twice as long as broad, all setose. Inferior antennæ less than half as long as superior; flagellum about 14-jointed, half as long as the peduncle. First pair of gnathopoda having the carpus and propodos subequal, the latter oblong, with an ill-defined oblique convex palm and a slender curved dactylos; dense rows of hairs occur on the extremity of the meros, and transversely on the lower side of the carpus and margins of the propodos, while the latter also bears numerous oblique or transverse rows of short spine-like hairs. Second pair of gnathopoda very large; basos deeply hollowed out in front, so as to form a groove for the propodos; ischium, meros, and carpos very short, the latter about three times as broad as long; propodos large, ovate, distally produced into a large curved tooth on each side of the articulation of the dactylos, terminal half of the lower surface with a deep groove to receive the dactylos, whole lower surface very densely fringed with two rows of long simple hairs; dactylos strong, arcuate, sinuously toothed on its inner margin, blunt. First and second pairs of pereiopoda slender, three
posterior pairs broader and more hirsute; third pair shortest. Posterior pleopoda having the rami subequal and densely fringed with hairs at their extremity. Telson having each division slightly hollowed out at the apex, with the inner edge acutely toothed, and two setæ springing from the hollow.
The integument is of a remarkably horny consistence.
Colour yellowish. Length 0.5 inch.
Hab. Only two specimens of this very distinct species were taken in the dredge in Port Pegasus. I have named it in honour of my fellow-worker and companion on the cruise, Mr. D. Petrie.