18 G. 0. SARS. CRUSTACEA. [norw. pol, exp. 



The posterior maxillae (see figs. 2 & 9) are likewise quite normal in 

 their construction. The basal part is rather voluminous and muscular, and 

 the 2 terminal lobes are comparatively narrow and strongly incurved. Both 

 lobes are densely hairy, and the somewhat larger outer lobe is, moreover, 

 armed at the tip with several strong spines. 



The maxillipeds (see figs. 2 & 10), as in other Hyperiida, are quite desti- 

 tute of palps. The broad, flattened basal part consists of a short common 

 root-joint, and 2 juxtaposed lamellar pieces, each carrying outside a single 

 seta, and projecting at the end inside in a short triangular lappet. These 

 lappets, which lie in close juxtaposition, and are fringed with short bristles, 

 undoubtedly answer to the basal lobes in other Amphipoda. It is likewise 

 indubitable that the large lamellae appended to the end of the basal part, 

 represent the masticatory lobes in other Amphipoda, exhibiting, as they do, 

 a very similar appearance. They are oblong oval in form, and, being mov- 

 ably articulated to the basal part, they may either be extended straight in 

 front, or be spread out, so as to diverge more or less widely. Along the 

 straight inner edge, there is a double row of strong spiniform bristles, and 

 each of the lobes also carries outside, at some distance from the tip, 2 

 similar bristles springing from a distinct ledge. 



The 2 pairs of gnathopoda (figs. 11, 12) are of essentially similar structure, 

 being considerably shorter and thicker than the pereiopoda, and also more 

 abundantly supplied with bristles. They are quite simple, without any trace of 

 a cheliform structure, the propodal joint being conically tapered, and carrying 

 at the tip the small dactylus. This joint is rather more produced in the 

 posterior than in the anterior pair; but in none of them is there any 

 distinctly defined palm. 



The 2 anterior pairs of pereiopoda (fig. 13) are of quite normal appear- 

 ance, and moderately slender. Of the joints, the carpal and propodal ones are 

 somewhat compressed, and are both provided along the posterior edge with a 

 row of short spinules. The dactylus is comparatively small and quite simple. 



The 3 posterior pairs of pereiopoda (figs. 14, 15) gradually diminish 

 somewhat in length, and are all distinguished by the peculiar arrangement of 

 the dactylus. The latter is strongly curved, finely denticulated along the 

 concave edge, and exserted in a very acute point. It is, moreover, retractile, 

 and capable of being received into a hollow formed by a cup-like projection of 



