REPOUT ON THE AMPHIPODA. 753 



of the former, to the latter, as Boeck recognises, he attributes a two-jointed palp. Boeck 

 unfortunately leaves the first maxillse undescribed in all the other seven species which he 

 places in the genus Metopa. 



Metopa nasutigenes, n. sp. (PI. XL.). 



Rostrum wanting, lateral lobes of the head very inconspicuous ; the postero-lateral 

 angles of the first three pleon-segments not rounded, but not very acute. 



Eyes round and bright, placed rather high up on the head ; the ocelli not numerous, 

 bright. 



Upper Antennse. — The first joint nearly twice as long as the two following united, 

 excavate beneath and distally prolonged to a point forming a cap over the second and 

 two-thirds of the third joint ; the second joint thicker and longer than the third ; the 

 flagellum scarcely longer than the peduncle, consisting of ten slender joints, which have 

 some apical cilia and long cylinders. 



Lower Antenna.— First joint a little inflated, gland-cone broad-pointed, third joint 

 short and curved, fourth joint scarcely as long as the fifth, both slender ; the flagellum of 

 eight slender joints, not quite so long as the peduncle, nor yet so long as the flagellum of 

 the upper antennse. 



Mandibles. — The cutting edge broad, with a denticle at the top, below this a 

 smooth rim, and below this an angled piece cut into six or seven teeth or denticles ; the 

 secondary plate short, with a rather broad edge, finely denticulate ; the spine-row of nine 

 short curved spines in two detachments of three and six ; a small process rises close 

 to the base of the palp ; the first joint of the palp longer than the third ; the second 

 more than twice as long as the first, with two slender spines or setse on the inner margin 

 and a longer one at its apex ; the very short and narrow third joint is tipped with a 

 spine more than twice its own length. The mandible here described, and figured in the 

 Plate on the left, is the right mandible, the secondary plate and sjjines showing through 

 the outer surface. 



First Maxillw. — Inner plate very small; outer plate short, with six spines on the 

 truncate apex, one very short, of tlie rest the outermost almost setiform, tlic innermost 

 finely pectinate, the intermediate ones with more or fewer lateral denticles ; the palp 

 broad, two-jointed, with three small spine-teeth on the distal part of the inner margin, 

 two on the apical margin with some intermediate spinules, and two submarginal setse. 



Second Maxillse. — The inner plate shorter than the outer, with three setules at 

 intervals on the inner margin, and three slender spines on the almost pointed apex ; the 

 outer plate widest distally, with nine long and three short spines round the serrate apical 

 margin, those on the outer slope being the shortest. 



Maxillip>eds. — The inner plates short and rather broad, with convex outer margins, 



(ZOOL. CHALL. KXP. — PART LXVU. — 1887.) Xxx 95 



