152 Cumacea: 18, Paraleuconidae, 1. Paraleucon, 19. Hemileuconidae, 1. Hemileucon 



than 2^*^, in d decidedly longer, flagellum 3-jointed, accessory 1-jointed. An- 

 tenna 2 of Q 3-jointed, -with 2 plumose setae on P* joint. Maxilliped 1 

 "with 2 small papilliform branchial sacs. Peraeopod 1, 2"*^ joint nearly as 

 long as rest of limb. Peraeopod 2 with 3*^ joint distinct. The single pair 

 of pleopods very small, the rami minute, 1-jointed, each carrying a long 

 plumose seta. Peduncle of uropods shorter than the endopod, which is shorter 

 than the exopod; endopod indistinctly divided into 2 subequal joints, with 

 about 12 spines on the medial margin and 2 apical spines. L. 9 2-9 mm, 

 d 2'4 mm. 



New Zealand, Lyttleton Harbour, depth 2 — 9 m; Akaroa Harbour, 11 m. 



19. Fam. Hemileuconidae 



1912 Hemileuconidae, T. Stebbing in: Ann. S. Afr. Mas., i\10v p. 133. 156. 



Pseudorostrum obliquely upturned in female, horizontal, truncate in 

 male. Telson wanting. Second antenna in male with short flagellum. 

 Peraeopods 1 — 3 in female, 1—4 in male with exopods. Pleopods wanting 

 in male. Uropods with endopod distinctly two-jointed. 



1. Gen. Hemileucon Caiman 



1907 Hemileucon, Caiman in: Tr. zool. Soc. London, «. I81 p. 32, 37. 

 Character of the genus included in that of the family for the present. 



2 species. 



Synopsis of species: 



j Carapace with a single horizontal ridge on each side . 1. H. uniplicatus 

 \ Carapace with two oblique ridges on each side .... 2. H. comes 



1. H, uniplicatus Calm. 1907 H. m., Caiman in: Tr. zool. Soc. London, v. 18 1 

 p. 37 t. 9 f. 21—25. 



Pseudorostral lobes straight, in Q slightly upturned, obliquely truncate, 

 in d horizontal, vertically truncate; antero-lateral angles produced to a tooth 

 in female, with slight serration in front and behind, in 6 without produced 

 tooth. Carapace with nearly half of the median carina serrate, a lateral 

 ridge on each side running from the end of the frontal lobe longitudinally 

 and curving upwards to join the hind margin. Antenna 1 with 3-jointed 

 flagellum and one-jointed accessory. Peduncle of uropods rather more than 

 two-thirds the length of the subequal rami, the second joint of the endopod 

 bearing the same proportion to the first joint. L. 9 2-6 mm, d 2*35 mm. 



New Zealand, Lyttleton Harbour, depth 2 — 9 ni; Akaroa Harbour. 11 m. 



2. H. comes Calm. 1907 H. c, Caiman in: Tr. zool. Soc. London, r. I81 p. 38 

 t.9 f. 26— 32. 



Pseudorostral lobes straight, in 9 directed obliquely upwards, acute; 

 antero-lateral corners produced into a tooth, with slight serration of the 

 lower margin behind it. Carapace with irregular serration of the median 

 carina anteriorly and a depression towards the rear, an oblique curved ridge 

 crossing the side of the frontal lobe and the pseudorostral lobe to the middle 

 of its lower margin and subparallel to this pair another pair starting from 

 near the median line and appi'oaching Init not reaching the antero-lateral 

 tooth. First antenna as in H. uniplicatus, second antenna of d* with flagellum 

 rather longer than in that species. Peraeopod 2 with 3<^ joint distinctl 



