I04 



CRUSTACEA MALACOSTRACA. II. 



peduncle very oblong; the single ramus half as long again as the peduncle, about four times as long 

 as broad, with the end cut off obliquely; on this terminal margin about seven fine, extremely long 

 seta are inserted, some of them about two and a half times as long as the ramus; no setse are found 

 on the lateral margins of the rami. Sixth segment as long as, or a little longer than, the two pre- 

 ceding segments together. — Uropods (fig. 4f) slender and long, from a little shorter to a little longer 

 than the three posterior segments combined; peduncle long, about as long as the fifth segment and 

 more than twice as long as deep; endopod with first joint a little or conspicuously longer than the 

 second; exopod very slender, half as long as the endopod and with its two joints equal in length. 



Length of a female with marsupium 2"™. 



Remarks. This small and slender species is easily distinguished from all North Atlantic or 

 Arctic forms hitherto known by its long and uniramous pleopods with very long setse. 



The mandibles are shown in fig. 4c; a description is scarcely needed beyond that given in the 

 remarks on the genus. 



Occurrence. Taken by the "Ingolf at a single station. 



Davis Strait: St. 25: Lat63°3o'N., Long. 54° 25' W., 582 fm., temp. 3.3°; 12 .spec. 



Leptognathiella n. gen. 



This genus is established on a new species which in a few features differs materially from 

 Leptognathia and Haplocopc. 



The body is extremeh- slender. The four-jointed antennnlse differ from those of Leptognathia 

 b)' having the second joint strongly produced abo\e (PI. X, figs. 5b and 5g) into a triangle overlap- 

 ping a part of third joint; besides second joint, seen from the side (figs. 5d and 5g), increases in depth 

 from the base to beyond the middle. (Mouth-parts unknown). Chelipeds normal, with the basal joint 

 having the hind margin of the well developed posterior protuberance free and rounded. Thoracic 

 legs built as in Leptognatliia, short; three anterior pairs thick. Pleopods wanting in the female. Last 

 abdominal segment with the posterior margin between the uropods feebly concave (fig. 5c); uropods 

 extremely long, curved downwards, biramous (figs. 5 f and 5!), with the endopod two-jointed, the short 

 exopod one-jointed. 



Remarks. Though the characters pointed out as generic are not very valuable, the aspect 

 of the animal is so different from that of the forms of Leptognatliia that the establishment of a new 

 genus seemed to me to be necessary. 



67. Leptognathiella abyssi n. sp. 

 (PI. X, figs. 5a-5i). 



Female (without marsupium). Body extremely slender, between ten and nine and a half 

 times as long as broad (fig. 5 a), broadest at the middle of the thorax which is a little broader than 

 the carapace and somewhat broader than the abdomen. — Carapace about as long as the second plus 



