BY GEO. M. THOMSON, F.L.S. 69 



anterior thoracic segments, as deep as the segments themselves, 

 the three posterior not half as deep ; fourth much wider than 

 those in fr-ont of it ; eyes small, oblong, close to the front 

 margiu of the cephalon ; upper antennae with joints of the 

 peduncle sub-equal ; lower, with the peduncle slightly shorter 

 than that of the upper pair ; maxillipeds, stout, with 4-jointed 

 palp ; both pairs of gnathopoda sub-equal, much compressed ; 

 terminal uropoda longer than the preceding pairs, inner branch 

 almost obsolete ; telson cleft into two portions. 



The length of the largest specimen was y% inch (14mm.) 

 The integument is generally smooth, but with a few minute 

 hairs on the back and sides of the abdominal segments. The 

 margins of the segments are also nearly quite smooth. 



The upper antenncs were, in both instances, about two-thirds 

 as long as the whole body ; the joints of the peduncle were 

 sub-equal in length, the middle one being slightly the longest ; 

 the flagellum, in most instances, was about twice as long as 

 the base, but in one example it was quite short. This may, or 

 may not, be a sexual difference ; I could detect no other dis- 

 tinction in the animal. The secondary appendage was very- 

 small and 3 -jointed. 



In the lower antenncB the peduncle was rather shorter than 

 the corresponding part in the superior pair ; the fifth joint was 

 rather shorter than the elongated fourth ; the flagellum was 

 composed of only some dozen joints, which were almost quite 

 destitute of setae, while those of the superior pair had only a 

 few minute ones at the extremities. 



The mandible palp (PI. iv., fig. 11), which is three-jointed, has 

 the basal joint, as u^ual, very short ; the second is the longest, 

 and has its lower margins broadened, flattened, and fringed in 

 their proximal part. This seems to form a kind of sheath or 

 hollow, into which the somewhat long terminal joint, which is 

 beautifully setose along its lower margin, can apparently be 

 folded. 



The first maxillcB (PL iv., fig. 12) have the outer plate ending 

 in about ten strong spines, the inner ones pectinately toothed 

 on the inside ; the inner plate is small, and carries four weak 

 plumose setsB near its extremity ; the palp is flattened, and 

 placed nearly at right angles to the rest of the limb, its elon- 

 gated second joint ends in a row of short spines. 



The second maxillce have the outer plate carrying numerous 

 set® at the extremity, while the smaller inner plate is fringed 

 along the whole inner border. 



The maxillipeds (PL v., fig. 2) are stout ; the plates on the 

 first joint are long, oval, and thickly fringed with setae at the 

 end; the plates on the second joint are larger, more rounded, 

 and thickly setose on their inner sides; the palp is strong and 

 four-jointed, with numerous setae on the inside and extremities; 



