Cumacea: 11. Diastylidae. 1. Diastylis 95 



of moderate length, 2"*^ joint spinulose, 5*i> shorter than 6**^, 7*^ than 5*^. 

 Peraeopod 2. 2'^^^ to 4*^ joints denticulate, 5*^^ subequal to 6*^ and 7^'' com- 

 bined. Exopod of uropod longer than endopod, which is half as long as 

 the peduncle, its 1^* joint scarcely equal to 2"*^ and 3'^ combined, spines on 

 the medial margin respectively 4, 2, 3. Colour pale carneous. L. Q 22-8 mm. 



N. Norway, depth 188 m; Franz .Joseph Land; Barents Sea, 226 — 414 m; Kara 

 Sea, 9—168 m; W, Greenland, 90— 377 m; lat. 79 » 58' N., 4B5 m; lat. 8lo 14' N., 150 m. 



11. D. armatus Norm. 1876 D. armata (nom. nud.), A. M. Norman in: Jeffreys 

 in: P. R. Soc. London, v. 25 p. 212 | 1879 D. a., A. M. Norman in: Ann. nat. Hist., ser. 5 

 0.3 p. 64 I 1887 D. a., H. J. Hansen in: Vid. Meddel., n39 p. 205 | 1900 D. a., Zimmer 

 in: Fauna arctica, v. I p. 420, 434. 



Pseudorostral lobes short, but ending acutely, with a pair of conspicuous 

 erect spines, behind each of these a longitudinal curved row of 4 spines, all 

 but the P* very small, and a single spine between each row and the serrate 

 antero-inferior margin, the surface of the carapace otherwise glabrous, with 

 sparse shallow pittings. Pedigerous segments together scarcely half as long 

 as the carapace, smooth, except that the side-plates of the b^^ are armed 

 with a spine, but not produced backw^ard. Pleon segments smooth, telson 

 longer than the peduncle of the uropods, its proximal section longer than 

 the preceding segment, lateral spines 3 small pairs, apical spines long. An- 

 tenna 1, with the 3 joints of the peduncle subequal. Peraeopod 1. 2"'^ joint 

 strongly spinose. Exopod of uropods rather longer than the endopod, the 

 medial margin of which has on its 3 joints respectively 2, 2, 1 spines. 

 L. 9 10 mm. 



Entrance of Davis Strait, lat. 59« 10' N., long. 50" 25' W., depth 3295 m. 



12. D. bispinosus (Stimps.) 1853 Cuma bispinosa, Stimpson in : Smithson. Contr., 

 ». 6 nr. 5 p. 39 | 1871 Diastylis qvadrispinosa, G. 0. Sars in: Ofv. Ak. Forh., i'. 28 nr. 1 

 p. 72 I 1871 D. q., G. O. Sars in: Svenska Ak. Handl., n. ser. v.9 nr. 13 p. 28 1. 10 

 f. 50—52, t. 11 f. 53—61 I 1873 D. qtiadrispinosa, S. I. Smith in: A. B. Verrill in: Rep. 

 U. S. Fish. Comm., v.l p. 507, 554 t.3 f.l3 | 18741). q., S. L Smith in: Tr. Connect. Ac, i'.3i 

 p. 28 I 1879 D. quadrispinosus, S. I. Smith in: Tr. Connect. Ac, v.oi p. 112 | 1883 D. 

 bispinosus, G. O. Sars in: Forh. Selsk. Christian., 1882 nr. 18 p. 57 | 1900 D. bispinosa 

 G. 0. Sars, Crust. Norway, v. 3 p. 47 | 1900 D. b., Zimmer in: Fauna arctica, v. i p. 421, 

 434 I 1912 D. quadrispinosa, Caiman in: P. U. S. Mus., r. 41 p. 605, 658. 



Pseudorostral lobes well produced, horizontal, acute. Carapace large, 

 with finely serrate anterior half of lower margin, a pair of conspicuous for- 

 ward pointing teeth, nodose in the cf, followed by a much smaller pair, flanking 

 the frontal lobes, and the back especially on the branchial regions beset with 

 spicules and short hairs, the hind margin raised. Pedigerous segments smooth, 

 5*'i with front margin crenulate, and small median tooth behind, postero- 

 lateral corners more produced in 6 than in 9 . Pleon segments 1 and 5 

 each with a pair of postero-dorsal teeth, a median serrate ridge on 2^^^ to S^^^ 

 in the c? and a pair of dorso-lateral ridges; telson shorter than peduncle 

 of uropods (Sars) or a little longer than it (in 6, Caiman), with 12 — 14 

 pairs of lateral spines. Eye distinct. Antenna 1, 3*^ joint longer than 2"^ 

 1^* equal to both combined. Maxilliped 1, with branchial leaflets in spiral 

 arrangement. Peraeopod 1, 2"^^ joint shorter than rest of limb, l^'^ shorter 

 than h^'^\ 5*^ than 6*^'\ Peraeopod 2, 2"*^ joint with strong spine at apex, 

 3^ with 2 such spines, 5*^ shorter than 6^'! and 7*^ joints combined. The 

 many-spined peduncle of uropods rather less than twice the exopod, rather 

 more than twice the endopod, in which the 1^* joint is rather less than the 



