316 COLLECnONS from MELANESIA. 



segments and fourth and fifth segments exist only on the dorsal 

 surface, but on the third extend down to the rounded postero-lateral 

 angles ; in the second segment the posterior margin ahove the 

 rounded postero-lateral angles is obscurely dentated. The lobes of 

 the terminal segment are subconical and tipped with one or two 

 setae. The eyes are oval, but very obscurely seen. The penulti- 

 mate joint of the peduncles of the superior antennae is slightly longer 

 and slenderer than the preceding ; the third joint, with which the 

 short accessory flagellum is articulated, is very short ; the flagella 

 aire themselves imperfect; the accessory flagella about 6-jointed. 

 The inferior antennae are much shorter than the superior ; the first 

 peduncular joint little more than half as long as the second, which 

 is about as long as the third j the flagella 12-14-jointed. The first 

 legs are slender and feeble ; the merus-joints very small, with pos- 

 terior acute lobe and tooth ; the carpus resembles the propus or 

 palm, having the posterior margin convex, rounded, and hairy ; the 

 dactyl is a little more than half as long as the palm. The second 

 legs have the carpus very short, propus considerably enlarged, longer 

 than broad, its distal margin oblique, slightly arcuated, and defined 

 by a small tooth ; dactyl slightly arcuated, and closing against the 

 distal margin of the propus. The three posterior legs are slender ; 

 the margins of the fourth to sixth joints with a few stiff hairs. 

 The uropoda are biramose, the rami in the penultimate and ante- 

 penultimate pairs subequal ; the last pair are wanting in the three 

 specimens I have examined. 



Another specimen from Port Jackson, 0-5 fms., which I refer 

 doubtfully to this genus (it having lost the head), and which I can- 

 not identify with any known species, has the body smooth and un- 

 armed, the first three postabdominal segments with a small spinule 

 at their postero-lateral angles; the terminal segment has the lobes 

 flattened and subacute distallj'. The first legs are small, with the 

 carpus and propus posteriorly arcuated, the carpus little shorter 

 than the propus. The second legs have the merus-joint short, but 

 little produced at its postero-distal angle ; carpus transverse, dilated 

 in its distal half, which equals the width of the palm at base ; palm 

 longer than broad, narrower distally, with the distal margin very 

 oblique, not acute, but presenting a broad surface, against which 

 the strong arcuate dactyl closes, and armed with four spines or lobes 

 as follows — one defining the postero-distal angle, a pair of small 

 spines in front of this, and a rounded lobe below the articulation of 

 the palm with the dactyl. The three posterior legs are rather 

 robust, with the basus-joints noti serrated ; the merus produced at its 

 anterior and distal angle. The outer ramus of the penultimate and 

 antepenultimate uropoda is slightly shorter than the inner ramus ; 

 the rami of the last pair subequal, broader and slightly shorter than 

 the preceding. 



This species, which may be designated provisionally M. crcissimana, 

 is apparently well distinguished by the form and dentition of the 

 palms of the second pair of legs. 



There is also in the collection a specimen which may belong to 



