66 Cumacea: 9. Leuconidae, 1. Leucon 



except for 2 denticles in line at apex of frontal lobe. Peraeopod 3 with 2 

 subequal narrow lanceolate appendages on the S^ joint. Peduncle of uropods 

 scarcely shorter than the rami, in which the endopod has a few more spines- 

 than in the Q and its 2""^ joint rather more than half as long as the first. 

 L. 6 mm. 



Coast of Norway, depth 19 — 94 m; Kattegat; Bay of Fundy; Gulf of St. Lawrence; 

 Greenland, depth 75 m; Spitzbergen, depth 1000 m; iat. 450 29' N., long. 55« 24' W.,. 

 depth 103 m; Nova Zembla, 90 m. 



4. L. australis Calm. 1907 L. a., Caiman in: Nat. antarct. Exp., v. 2 Crust. 

 Cum. p. 1 f. 1— 3. 



Pseudorostral lobes very slightly upturned, acute, not denticulate; 

 antero-lateral corners triangular, lower margin behind them serrate for a short 

 distance. Median carina of carapace closely serrate from front to hind 

 margin. Telsonic segment short, pentagonal, obtusely triangular between 

 bases of uropods. Antenna 1, accessory flagellum longer than first joint of 

 principal. Peduncle of uropods slightly shorter than the subequal rami, 

 endopod with 1^* joint twice as long as 2"^, carrying 8 spines on medial 

 margin, 2°*^ joint having 3 on medial margin and a larger one on apex, 

 L. 9 3-5 mm. 



Antarctic. 



5. L. fulvus 0. Sars 1865 L. f., G. 0. Sars in: Forh. Selsk. Christian., 1864 

 p. 180 I 1886 L. f., G. 0. Sars in: Norske Nordhavs-Exp., v. 6 nr. 15 p. 19 1 1900 L. f.. 

 G. O. Sars in: Crust. Norway, «;. 3 p. 32 t. 24 ] 1900 L. f., Zimmer in: Fauna arctica, 

 v.\ p. 416 I 1908 i. /"., Zimmer in: Ergeb. Tiefsee-Exp., w. 8 p. 177, 178 | 1911 L. /"., 

 Stappers in: Camp. arct. Orleans, Crust. Malac. p. 105 t. 4 f. 8. 



Q . Pseudorostral lobes slightly upturned to apex in dorsal view 

 narrowly truncate, laterally denticulately truncate ; autero-lateral corners acutely 

 produced with slight serration adjoining. Median carina of carapace denti- 

 culate from front to behind the middle and after an interval reappearing 

 to the rear. Peraeopod 1, 6*'! joint nearly as long as 5^^. Peduncle of 

 uropods subequal to the subequal rami, 2^'^ joint of endopod two-thirds as- 

 long as 1 ®S 1®* with 6 spines on medial margin, 2"*^ with 4 and a very long, 

 apical spine. Colour bright orange. L. scarcely 5 mm. 



d. Pseudorostral lobes obtusely rounded at apex with its lateral 

 border smooth; antero-lateral corners smoothly rounded, preceded and followed 

 by serration. Carapace quite smooth, with minute denticle at apex of frontal 

 lobe. Peraeopod 3, 3'^ joint with 2 comparatively short, falciformly curved 

 appendages (Sars), 4 lanceolate appendages, not very long, slightly incurved, 

 3 of them subequal (Stappers). Uropods more elongate than in 9 , spines 10 

 and 6 on joints of endopod, 2^*^ joint nearly four-fifths as long as 1^*. 

 Colour paler than in 9 . L. 5-5 mm. 



Lofoten Islands; depth 11—23 m; Finraark; Iceland; Spitzbergen; Nova 

 Zembla, 90 m. 



6. L. nasioa (Kroyer) 1841 Cuma «., Kroyer in: Naturh. Tidsskr., ?-. 3 p. 524, 

 532 t. 6 f. 31— 33 | 1846 iewcow n., Kroyer in: Naturh. Tidsskr., ser. 2 «. 2ii p. 189, 209 

 t. 2 f. 5a, b I 1849 L. n., Kroyer^ (Petersen del.) in: Voy. Nord, Crust, t. 3 f. 2a— o | 

 1855 L. w., W. Liljeborg in: Ofv. Ak. Forh., v. 12 p. 121 | 1865 L. nasicus, G. 0. Sars 

 in: Forh. Selsk. Christian., 1864 p. 178 | 1875 L.tiasica, Aug. Metzger in: Jahresber. 

 Comm. D. Meere, «. 2/3 p. 286, 308 | 1877 L. n., Meinert in: Naturh. Tidsskr., ser. 3 v. 11 



