Ir2 CRUSTACEA MAiACOSTRACA. III. 



lateral angles rounded, and the postero-lateral angles produced into oblong processes directed some- 

 what outwards, much backwards and considerably downwards; the posterior margin between the base 

 of these processes a little convex, and the lateral margins slightly converging from rather near the 

 base to somewhat from the end. - - In the male the abdomen (fig. 6 e) is proportionately broader than 

 in the female, with the major proximal part of the lateral margins somewhat convex, and the posterior 

 margin more convex than in the female. - - The operculum in the female posteriorly broadly rounded ; 

 in the male (fig. 6 i) each of the pleopods of first pair tapers conspicuously in breadth from somewhat 

 from the base to considerably beyond the middle, and then the outer margin suddenly turns consider- 

 ably outwards, so that the distal part of the pleopod is a rather large triangle, with the posterior 

 margin a little convex. - - Uropods (fig. 6 i) very peculiar, considerably less than half as long as the 

 abdomen; basal joint very large, with the inner margin straight and lying close at the median line 

 of the animal, so that the peduncles of the uropods completely overlap the anal doors when seen from 

 below; endopod more than half as long again as the peduncle, slender; exopod wanting. 



Length of a female without marsupium 2-1 mm., of the male 1-8 mm. 



Remarks. D. longispinum has the epimera at the four anterior thoracic segments produced 

 into longer processes than in any other species hitherto known, though in this character it shows affinity 

 to D. simile and the male of D. gracilipes. The sculpture on the surface of the animal is very char- 

 acteristic of D. longispinum. The two anterior pairs of legs are somewhat similar to those in D. simile, 

 though a little more slender and elongate. But in the very broad peduncles of the uropods and in their 

 inner margins lying close at the median line D. longispinum differs sharply from all other species. 



Occurrence. Taken by the "Ingolf" at its deepest station in the warm area. 



South of Davis Strait: Stat. 38: Lat. 59i2' N., Long. 5io5' W., 1870 fath., temp. 1-3; 4 spec. 



70. Desmosoma simile n. sp. 

 (PI. X, figs. 7 e 7 e). 



Female. First thoracic segment about as long as the second or the third, and a little shorter 

 than the fourth (fig. 7 a). The epimera at these segments anteriorly produced into very oblong-triangular, 

 moderately long processes, each terminating in a distinct, small and short spine; the processes decrease 

 a little in length from first to fourth pair, and the first pair are considerably shorter than their seg- 

 ment. Fifth segment more than half as broad again as long; the anterior margin is straight, the 

 antero-lateral angles produced into very conspicuous, triangular, acute processes directed outwards, 

 and the anterior part of each lateral margin is somewhat concave. 



First pair of legs (fig. 7 b) rather slender; fifth joint about three and a half times as long as 

 deep, at the lower distal angle with two very strong, stiff setae somewhat shorter than sixth joint, 

 while two somewhat shorter, stiff setae are found respectively before and beyond the middle of the 

 lower margin; sixth joint with about three setae on the lower margin. -- Second pair of legs (fig. 7 c) 

 rather slender; fifth joint nearly three and a half times as long as deep, increasing slightly in depth 

 from the base outwards; its lower margin has five stiff setse, the two distal, placed at the angle, are 

 thick and very long, the longest even considerably longer than the sixth joint; furthermore the outer 



