68 



14. Leptostylis longimana, G. 0. Sars. 



(PI. XLVIII). 

 Diastijlis longimana, G. 0. Sars. Om den aberrante Krebsdyrgruppe Cumacea, p. 48. 



Specific Characters. Female. Body comparatively slender, though having 

 the anterior division considerably tumefied and rounded oval in form. Carapace 

 large and deep, more than twice as long as the exposed part of the trunk, and 

 slightly vaulted above, surface perfectly smooth throughout, and only clothed 

 with scattered small hairs; pseudorostral projection of moderate size, triangular, 

 subrostral corners obsolete, lower edges of carapace abruptly curved in the 

 middle, with the anterior half minutely denticulate. Epimeral parts of the 3 

 posterior pedigerous segments comparatively small and rounded off behind. Tail 

 (exclusive of the terminal appendages) exceeding the length of the anterior division 

 and very slender. Superior antennae rather elongated, the peduncle extending far 

 beyond the tip of the pseudorostral projection, its last joint scarcely shorter than 

 the 1st, but much narrower, and, like the 2nd, clothed on both edges with slender 

 bristles. First pair of legs exceedingly slender and elongated, and, when fully 

 extended, exceeding half the length of the body, basal joint occupying scarcely more 

 than l / z of the length of the leg, and without any spinules, penultimate joint of 

 extraordinary length, fully equalling that of the 3 preceding joints combined, last 

 joint comparatively short, not attaining even l / 3 of the length of the penultimate 

 one; 2nd pair likewise rather slender and much curved, basal joint comparatively 

 short, last joint very slender, exceeding the length of the antepenultimate one; 3rd 

 and 4th pairs rather narrow, with the rudimentary exopodite easily observable and 

 carrying a single apical bristle. Uropoda much elongated, with the inner ramus 

 very narrow, and exceeding the outer by its last joint, 1st joint longer than the 

 other 2 combined, spinules of the inner edge only 5 in number (3 on the 1st, 

 and 1 on each of the last 2 joints), apical spine very slender, almost setiform. 

 Telson not attaining even the length of the last caudal segment, and rather thick 

 at the base, distal part abruptly narrowed and, as in the other species, provided 

 with only a single pair of lateral spinules near the tip, apical spines somewhat 

 larger, and extended straight behind. Colour whitish. Length 5 J /2 mm. 



Adult male scarcely more slender than the female, but having the 

 carapace less deep, and the pseudorostral projection more prominent. Tail scarcely 

 exceeding in length the anterior division, and very narrow, unarmed, terminal 

 appendages scarcely different from those in the female. Length about 5 mm. 



Remarks. This form was first described by the present author as a 

 species of the genus Dlastylis, the specific name proposed being derived from the 



