CRUSTACEA MALACOSTRACA. III. 79 



Remarks. M. abyssicola is easily separated from M. spinifera by 3-johited antennulae, consider- 

 ably shorter antennae, the long snbhorizontal ventral process from first thoracic segment, while the 

 other segments have only a carina but no processes, by the shape of the terminal part of the abdomen, 

 the small and short female operculum, etc. 



Occurrence. Taken by the "Ingolf" at three very deep stations in the warm area. 



Davis Strait: Stat. 37: Lat. 6o°i"j' N., Long. 54°o5' W., 1715 fath., temp. 1-4.°; 3 spec. 



South of Davis Strait: Stat. 38: Lat. 59°i2' N., Long. 5i°c>5' W., 1870 fath., temp. 1-3°; ab. 10 spec. 

 — - — Stat. 22: Lat. 58°io' N., Long. 48°25' W., 1845 fath., temp. 1-4°; 6 spec. 



48. Macrostylis elongata n. sp. 



(PI. VII, figs. 3 a- 3 g). 



Female (without marsupium). Slender, not fully five times as long as broad. — Head distinctly 

 larger and especially longer in proportion to the anterior thoracic segments than in the preceding 

 forms. - - Antennulae moderately short, slender, 3-jointed (fig. 3 b) ; all three joints subequal in length, 

 and the terminal joint with a somewhat broad sensory fiiament (s). — Antennae very short, shorter 

 than the length of the head (fig. 3 b) ; penultimate joint of the peduncle distinctly shorter than the 

 terminal joint; flagellum of the left autennula in my single specimen 4-jointed, that of the right 

 2-jointed. — Distal joints of the maxillipeds nearly as in M. spinifera. 



The thorax differs in outline (fig. 3 a) considerably from that in any of the other species, because 

 its fourth segment is much narrower than the third, the fifth segment somewhat elongate, longer and 

 broader than the fourth, and the sixth segment a little longer than in the two preceding species; the 

 three posterior segments are a little produced at the postero-lateral angles, and each protuberance is 

 somewhat broadly rounded (fig. 3 f), with a small spine. First thoracic sternite at the middle with a 

 median long and strong process directed forwards and downwards; each of the two following sternites 

 with a much smaller process; fifth and sixth sternites each with a small process directed downwards 

 and backwards, but on fourth and seventh sternites no process was found in the specimen. 



The thoracic legs (figs. 3 c — 3 e), especially the posterior pairs, more slender than in the preced- 

 ing forms. Third pair (fig. 3 c) with third joint more than twice as long as broad, and its dorsal spine 

 somewhat short, but strong and a little curved; the upper setae on fourth and fifth joints, excepting 

 the most proximal setae on fourth joint, very strong, spiniform, moderately long and conspicuously 

 bifid at the end. The two posterior pairs (figs. 3d and 3 e) subequal in length, very slender; sixth 

 pair has the sixth joint more than half as long again as the fourth, seventh joint very long, about as 

 long as fourth joint and a little longer than the thin claw; seventh pair has setae, probably natatory, 

 along both margins of second joint (fig. 3 e). 



Abdomen seen from above (figs. 3 a and 3 f ) slightly longer than the sum of the posterior seg- 

 ments, a little narrower than in M. spinifera, but otherwise nearly of the same shape, having the 

 posterior part produced as a long, moderately broad lobe, and each half of the posterior margin inside 

 the base of the uropod rather concave, while the end is moderately broadly rounded. — Seen from 

 below (fig. 3 g), the operculum is large, occupying the major part of the lower surface, almost twice 



