74 



rather slender. Superior antennae of normal appearance. Inferior antennae in 

 female extremely small, uniarticulate, with a single apical seta; those in male 

 generally shorter than the body. Branchial apparatus with the gill-elements rudi- 

 mentary. Third pair of maxillipeds pediform, with the outer corner of the basal 

 joint not produced, and carrying a single strong plumous seta. First pair of 

 legs of normal structure, and not much produced; 2nd pair with the terminal 

 joint in male more or less distinctly hooked at the tip. Anterior pair of pleopoda 

 rather large, with the basal part lamellar and carrying strong setae inside, rami 

 confluent; posterior pair very small, claviform, without setae. Uropoda moderately 

 slender, rami narrow lanceolate, the inner one the longer. 



Remarks. This genus was established by the present author in the year 

 1864, to include a small Cumacean found off the Lofoten Islands, and at that 

 time regarded as new, but subsequently identified with a form very imperfectly 

 described and figured by P. van Beneden as Leucon cercarkt. In the restriction 

 of the genus here adopted, it comprises only 3 other species, viz., the Mediter- 

 ranean form, P. ciliata G. 0. Sars, the Caspian form, P. cercaroides Or. 0. Sars, 

 and a new Norwegian species, to be described farther on. 



i. Pseudocuma eerearia (v. Beneden). 



(PI. Ll & LIT). 



Leucon eerearia P. v. Beneden, Kecherches sur la Faune littorale de Belgique. 



Crustaces, p. 85, PL IV. 



Syn : Pseudocuma bistriata, G. 0. Sars. 

 ? Cyrianassa lowgicornis, Sp. Bate (male). 

 Ouma bella, Meinert. 



Specific Characters. Female. Body more slender than in the other species, 

 with the anterior division considerably vaulted dorsally and ovate in form. Cara- 

 pace somewhat exceeding in length the exposed part of the trunk, and sloping 

 considerably in front, lateral faces sculptured with 2 distinct oblique plicae 

 extending from the hindmost part of the branchial regions to the subrostral 

 corners, the latter unarmed; pseudorostral projection rather prominent, termi- 

 nating in an acute point. Tail very slender, slightly exceeding in length the 

 anterior division. First pair of legs scarcely longer than the carapace, basal 

 joint occupying about half the length of the leg, the 3 distal joints rapidly dimi- 

 nishing both in length and width, terminal joint very narrow, linear; 2nd pair 

 with the terminal joint conically tapered and about the length of the antepenulti- 

 mate one; 3rd and 4th pairs not very slender, rudimentary exopodite distinctly 



