Cumacea: 11. Diastylidae, 1. Diastylis, 2. Brachydiastylis 107 



Pseuclorostral lobes moderately long, horizontal, acute, antero-lateral 

 angles barely indicated. Carapace beset with spinules, larger in front, and 

 lining the more or less prominent ridges, of which one pair, nearly hori- 

 zontal, adjoins the pseudorostral lobes and is met l)y a curved pair from the 

 lower margins; to these are added an oblique pair and a medio-dorsal longi- 

 tudinal pair. The eyelobe is broader than long, with obscure corneal areas. 

 Pedigerous segments 1, 2, 5 have the anterior margin finely serrate; postero- 

 lateral corners of the 5''' obtuse. Pleon segments 1 and 5 each with a pair 

 of small dorso-lateral teeth. Telson about twice as long as the 6*^^ segment, 

 with about 9 pairs of lateral spinules. Antenna 1, 3*^ joint rather longer 

 than 2^^. Maxilliped 3, 2"'^ joint distally wider than 3'^. but not produced. 

 Peraeopod 1, 2"*^ joint spinose. not quite so long as rest of limb, 5*^ joint 

 a little shorter than 6**> and longer than 7*^. Peraeopod 2, 5*^ joint subequal 

 to 1^^^ and 7**^ combined. 3*^ and 4^^^ pairs in 9 without exopods. Peduncle of 

 uropods about as long as the telson in 9 , shorter in young cS • rami unknown. 

 L. ovigerous 9 12*2 mm, d juv. 9 mm; 9 with rudimentary oostegites, flatter 

 front part of carapace, body plunosely hirsute carapace, 15-6 mm. 



Shahafka Cove, Kodiak, Alaska; hirsute variety, Okhotsk Sea, E. of Sakhalin 

 Island, depth 137 m. 



D. ambigua Lilij. 1886 D. a. (descr. nulla), W. Lilijeborg in: C.W. S. Aurivillius 

 in: Bih. Svenska Ak., I'.ll nr. 4 p. 41. 



L. 12 mm. 



From N. E. of Tromso or West Finmark. 



D. quadri-plieata Lilij. 1886 L). q.-p. (descr. nulla), W. Lilijeborg in: 0. W. 

 .S. Aurivillius in: Bih. Svenska Ak.. t'. 11 nr. 4 p. 41. 



L. 12 mm. 



From N. E. Tromso or West Finmark; at Baddern, between depths 75 and 94 m. 



2. Gen. Brachydiastylis Stebbing 



1912 Brachydiastylis, T. Stebbing in: Ann. S. Afr. Mus., ?;. lOv p. 176. 



Pseudorostral lobes upturned in the female and the carapace siiort, 

 the third and fourth pedigerous segments tending to coalesce, and the third 

 peraeopod widely separated from the second in the ovigerous female. 

 Antenna 1 with third joint of peduncle the longest. Second joint of third 

 maxilliped distally expanded, third not wider than fourth. Third and fourth 

 peraeopods of female without rudimentary exopods. Exopod of uropods much 

 longer than endopod. 



1 species. 



1. B. resimus (Kroyer) 1846 Cuma resima, Kroyer in: Naturhist. Tidsskr., ser. 2 

 V. 2ii p. 165, 206, 21l.<t. 2 f. 2a, b | 1849 C. r., Kroyer in: Voy. Nord Crust., t. 3 f. la— p | 

 1871 Diastylis r., G. 0. Sars in: Svenska Ak. Handl., n. ser. v.9 nr. 13 p. 5 | 1880 

 D. r.. Stuxberg in: Bih. Svenska Ak., v. 5 nr. 22 p. 22 | 1883 D. resimus, G. 0. Sars in: 

 Forh. Selsk. Christian., 1882 nr. 18 p. 12,58 | 1893 Diastylopsis resima, T. Stebbing in: 

 Int. sci. Ser., v. 74 p. 311 j 1894 Diastylis resimus, A. M. Norman in: Ann. nat. Hist., ser. 6 

 i-. 13 p. 277 I 1900 Diastylopsis resima, G. O. Sars, Crust. Norway, u3 p. 65 t. 47 | 1900 

 D. r., Zimmer in: Fauna arctica, v.l p. 426 (with synonymy) | 1901 D. r., T. Scott, in: Rep. 



