TWO SPECIES OF CUMACEA IN NEW ZEALAND. 267 



long as those succeeding it ; it is elongated and produced on its 

 outer margin iuto a long acute lamella, w^hich bears a row of 

 spines on its inner edge. The ischium bears a row of short 

 plumose setae on its inner margin, and has its outer extremity 

 produced into a blunt curved lamella which ends in a single 

 plumose seta. The meros is very short, and bears only one or 

 two setae. The two remaining joints are bent almost back on 

 the meros (fig. 14), so that their structure can hardly be made 

 out until they are dislocated : the propodos ends in a strong 

 spine and two or three short setae. The exopodite of this 

 limb is about half the length of the gnatliopod, and, exclusive of 

 the base, is 7-jointed ; each of the joints bears two long beautifully 

 plumose set£e. 



The first pair of legs (fig. 15) exhibit a modification of the 

 structure which characterizes the three pairs of limbs anterior to 

 them. The prolongation of the basos is very slender and acute; 

 it shows the coarse granular structure described by Sars as 

 occurring in O. australis, and is destitute of setae or spines, as 

 indeed are all the joiuts except the last. The ischium is not 

 produced as it is in the second gnathopods, while the remaining 

 joints are elongated and slender ; the last bears a few setae at its 

 extremity. 



The four pairs of amiulatory legs diminish gradually in size 

 posteriorly, and are not very dissimilar in form. In the spe- 

 cimen dissected the relative lengths were 1 mm., 0"93 mm., 

 0*87 mm., and 0'7l mm. In the first of these {second pair of 

 legs) the basos is long and narrow, the ischium is very short and 

 bears a long plumose spine at its extremity ; the meros, which 

 is somewhat longer, also bears a plumose spine ; the carpos has 

 three spines at its extremity, each of which is finely pectinated 

 or toothed along one of its margins (fig. 16); the dactylos is 

 nearly twice as long as the propodos, and ends in three strong 

 spines. 



Thepleopoda are wanting in the females, as usual in the Cumacea. 

 In the males five pairs are present, and are very similar in form, the 

 last pair being somewhat the smallest. Each pair consists of a 

 strong basal joint and two branches (figs. 20-24). The basal joint 

 is about three times as long as it is broad, and bears on its inner 

 edge, near the middle, a short row of spines which are curiously ser- 

 rated at their apex. The outer branch is 2-jointed, the last joint 

 being oval in shape and fringed round its end with long setae. 



