24 G. 0. SARS. CRUSTACEA. [norw. POL. EXP. 



The posterior gnathopoda (fig. 2) exhibit the structure characteristic of 

 the Lysianassidce, being extremely slender and flexible, and very frequently 

 bent in such a manner as not to be visible externally. The 2 outer joints 

 are densely clothed with fine hairs, and carry, moreover, fascicles of slender 

 bristles. The propodal joint is oblong oval in form, and exceeds half the length 

 of the carpal one. It is narrowly truncated at the tip, and carries on the 

 upper corner the very small curved dactylus (see fig. 3 a). 



The 2 anterior pairs of pereiopoda (figs. 3, 4) are of moderate length, 

 and quite normal in structure. 



The 3 posterior pairs (figs. 5, 6, 7), on the other hand, are more elongated 

 than in most other I/ysianassidce, and slightly increase in length posteriorly 

 The basal joint is rather large and laminar, being obliquely rounded in the 

 anterior pair (fig. 5), and in the 2 other pairs (figs. 6 & 7) more pyriform in 

 outline. In all 3 pairs, the posterior edge is for some distance minutely serrate, 

 and the infero-posteal corner drawn out to an obtusely rounded lobe. The outer 

 part of the legs is fringed on both edges with fascicles of short spines, and has 

 the propodal joint rather elongate and sublinear in form. The dactylus is of 

 moderate length, and but slightly curved. 



The branchial lamellae are present at the base of all the legs, except the 

 1st pair (the anterior gnathopoda), and are of moderate size, with a small 

 secondary lobe inside (see figs. 2 — 7). The incubatory plates (not fully 

 developed in the specimen examined) are very narrow. 



The pleopoda are of quite normal structure. 



The uropoda, however, somewhat differ from those in other Lysianas- 

 sidce. The two anterior pairs (figs. 8, 9) have both rami lanceolate in form, 

 terminating in a simple, naked point, and carying on the edges short scat- 

 tered spinules, the outer ramus in both pairs being shorter, and also narrower, 

 than the inner. The last pair (fig. 10), as usual, have the basal part shorter 

 and thicker than in the 2 preceding pairs, whereas the rami are comparatively 

 larger, so as to project beyond those of the above-mentioned pairs. The inner 

 ramus is uniarticulate and lanceolate in form, with the inner edge densely 

 setiferous; the outer ramus, on the other hand, is distinctly biarticulate, the 

 distal joint being spiniform, and projecting a little beyond the inner ramus. 



The telson (fig. 11) is remarkable from its large size, as it exceeds half the 

 length of the urosome. It is narrow lanceolate m form, and cleft nearly to 



