NO. B.] ACCOUNT OF THE SPECIES. 



The buccal mass is more or less completely concealed laterally by the 

 anterior coxal plates, so that only the mandibular palps and the maxillipeds 

 are partly exposed (see fig. 1). 



The anterior Up is simple, rounded, and the epistome not projecting. 



The posterior lip (fig. 8) has the lateral lobes narrowed in front, and 

 slightly bilobular at the tip, each being produced behind to a conical process. 



The mandibles (figs. 9, 10) are very strong, with the masticatory part 

 somewhat incurved and divided into a narrowly truncated cutting part, and 

 a short, but distinctly prominent molar expansion, exhibiting at the tip 

 a finely fluted triturating surface. The palp (see fig. 9) is greatly devel- 

 oped, considerably exceeding the body of the mandible in length, and has the 

 last joint falciformly curved. 



The anterior maxillae (fig. 11) exhibit the usual structure. The mastic- 

 atory lobe is rather prominent, and carries at the tip several strong spines, 

 the inner edge being covered with fine hairs, and moreover armed with from 

 3 to 4 somewhat smaller spines. The basal lobe is comparatively small, with 

 only 2 plumose setse at the tip. The last joint of the palp is but slightly 

 dilated and is, as usual, denticulated at the tip. 



The posterior maxillae (fig. 12) have the inner lobe rather small, scarcely 

 more than half as large as the outer, both exhibiting the usual dense clothing 

 of setae. 



The maxillipeds (fig. 13) on the whole agree in structure with those in 

 the other species of the genus. The masticatory lobes are not vevy large, 

 scarcely reaching beyond the middle of the penultimate joint of the palp, and 

 are oval in form, with the inner edge minutely serrate. The basal lobes are 

 narrowly truncated at the tip, and carry the usual setae. The palps are 

 rather large, with the joints somewhat expanded and densely setiferous. 



The anterior gnathopoda (fig. 14) are somewhat less strong than in the 

 type species, with the outer part scarcely longer than the basal joint. The 

 propodos is about the length of the 2 preceding joints combined, and is obliquely 

 truncated at the tip, exhibiting a well defined palm, which is armed at the 

 inferior corner with several strong denticles. 



The posterior gnathopoda (PI. V, fig. 1) differ from those in the type 

 species chiefly in the propodos being somewhat broader and more trans- 

 versely truncated at the tip, with the lower corner scarcely at all produced, 



