49 



being conspicuously constricted at the base of the caudal fan, all segments very 

 sharply defined, and having distinct rounded epimera. Superior antennae in female 

 much shorter than the cephalon, first joint of the peduncle about the length of 

 the other 2 combined, flagellum not exceeding in length the last peduncular joint, 

 conic in form, and exhibiting 1 or 2 extremely small terminal joints; those in 

 male more than twice as large, and, as a rule, reflexed, last joint of the peduncle 

 very movably articulated to the 2nd, and gradually widening distally, flagellum 

 fully as long as the peduncle, and rather thick at the base, being composed of 

 about 10 articulations, each provided with a dense whorl of long sensory filaments, 

 whereby the outer part of the antenna acquires a brush-like appearance. Inferior 

 antennse of same structure in the two sexes, rather stout, flagellum very small, 

 with 3 — 4 extremely minute terminal joints, carrying a dense brush of bristles. 

 1st pair of legs likewise of a similar appearance in the two sexes, propodos large, 

 oval, set obliquely on the short carpus, palm deeply concave, and armed with a 

 row of flattened denticles, thumb-like process very prominent. The 2 succeed- 

 ing pairs of legs with the propodos in female comparatively short, subquadrangular, 

 palm defined below by a distinct angle, that in male much longer, pyriform, 

 palm occupying the whole lower edge. First pair of pleopoda having the outer 

 plate oblong oval, gradually widening distally. Uropoda with the inner ramus 

 rather narrow, and reaching considerably beyond the telson, terminal joint about 

 the length of the proximal one, and having at the tip a dense brush of slender 

 bristles, outer ramus broadly c.jrdiform, arching over the base of the telson, so 

 as almost to meet the corresponding ramus on the other side in the middle, 

 edge smooth, only clothed with scattered bristles. Telson in male broad, scarcely 

 more than twice as long as it is broad, in female considerably narrower, edges 

 smooth, except at the tip, which carries 2 long and 2 short bristles. Colour a 

 pure white. Length of female 7 mm., of male 8V2 mm. 



Remarks. — By its extremely slender, filiform body, this form is easily re- 

 cognized from most other Anthuridw, though the species of Antlielura and Hyssura 

 in this respect would seem to approach it. On account of its pure white colour 

 and comparatively small size, it may at first sight be mistaken for a Tanaid. 



Occurrence. — I first detected this form at Hvitingso, outside Stavanger, 

 in a depth of 150 — 200 fathoms, and have subsequently taken it in the inner 

 part of the Stavanger Fjord at Jelse, as also rather plentifully in the Trondhjem 

 Fjord in similar depths. It is a rather sluggish animal, creeping slowly along the 

 bottom. At times it is seen to bend its body almost in a circle; but I have 

 never seen it make any attempt to swim, though the structure of the pleopoda 

 seems to admit of such a motion, at least in the male sex. 



Distribution.— -Stat. 22 of the Porcupine Expedition, located off Lisbon 

 (Norm. & Stebbing). 



7 — Crustacea. 



