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DISCOVERY REPORTS 



Fig. 5. Serolis kempi, n.sp., ^: x 6. 



Description. This collection contains adult males and females, the latter in both the 

 breeding and non-breeding phase. An adult male measures 15 mm. in length and 

 14 mm. in breadth, and an adult female 15 mm. in length and 13 mm. in breadth. 



The body (Fig. 5) is broadly oval, 

 slightly longer than broad and slightly 

 keeled. The head is about one and a half 

 times as wide as long, shield-shaped in 

 outline, with a very small rostral process 

 between the bases of the antennules: 

 behind this process a well-marked trans- 

 verse ridge extends laterally to the sides 

 of the cephalosome. The portion of the 

 head between the eyes is convex and 

 divided into two areas by a slight groove ; 

 an anterior one bearing two rounded 

 prominences and a posterior larger one, 

 divided into three oval prominences, the 

 central of which is smaller than the two 

 lateral : this area extends for some distance 

 behind the eyes. 



The eyes are large, about half the length of the head, reniform in shape and containing 

 black pigment. 



The second thoracic somite is fused with the head as in all the species of Serolis. The 

 lateral portion bears two transverse ridges on each side, a small anterior one which is 

 continuous with the anterior one already described on the head, and a second which 

 extends laterally from near the posterior angle of the eye, a point about half-way between 

 the anterior and the posterior margins of the cephalosome. Each of the third to the 

 seventh thoracic somites is produced into a short but distinct median dorsal spiniform 

 process ; that of the fifth somite is considerably larger and longer than those of the other 

 somites and projects backwards to about the middle of the sixth somite. Low eminences 

 are present, one on either side of each of the thoracic somites, just within the junction of 

 the tergum with its coxal plate. The coxal plates are well developed and are sparsely 

 fringed with short hairs, those of the first three free somites are marked off by distinct 

 sutures. The coxal plates of the seventh thoracic somite are produced backwards to a 

 point a short distance behind the level of the bases of the uropoda. 



The abdomen (Fig. 5) consists of three free somites and a terminal one, and each of 

 the three somites has a slight median dorsal process corresponding with those of the 

 thoracic somites. The pleural plates of the second segment are well produced backwards 

 beyond the coxal plates of the seventh thoracic somite to about the level of the basal 

 joint of the uropod; those of the third segment are longer and reach beyond the basal 

 joint of the uropod. The terminal segment, which is broader than long, has a well- 

 developed spine in the anterior median dorsal line ; this is followed by a slight median 



