148 Annals of the South African Museum. 



depth 57 m. ; lat. 32 53' 30" S., long. 28 11' 00" E., depth 75 m. ; 

 Sebastian Bluff, W.N.W. 2 miles, depth 44 m. 



ADIASTYLIS, n. g. 



This genus is separated from Diastylis as having the proximal 

 division of the telson long and cylindrical, while it is distinguished 

 from Makrokylindrus by having the short post-anal part furnished 

 with lateral spines. It contains the new species A. acanthodcs, 

 together with A. longipes (Sars), 1871, A. costatus (Bonnier), 1896, 

 both transferred from Diastylis, and A. longicaudatus (Bonnier), 

 189(3, originally referred to Leptostylis, from which it differs 

 strikingly by the length of the telson. 



It is not improbable that the species agree in having the first 

 peraeopods elongate, but those limbs were mutilated in the speci- 

 mens from which A. costatus and A. acanthodes were described a 

 calamity to which the front legs are especially liable when they are 

 of great length. 



ADIASTYLIS ACANTHODES, n. sp. 

 Plate LIII. 



The present species is unfortunately known only in the male sex. 

 The carapace of the single specimen was damaged, the first legs 

 were defective from the end of the second joint and the endopod 

 of the uropods from what appears to be the end of the second 

 joint. 



The pseudorostral lobes meet for some distance in advance of the 

 apparently sightless eyelobe, being produced acutely as far as the 

 end of the first joint of the first antennae ; their upper surface is 

 diversified, in common with the rest of the carapace, with numerous 

 denticles of various sizes. The carapace seems to be devoid of 

 ridges. The five pedigerous segments are free, much denticulate, 

 each with a pair of conspicuous dorsal teeth, unless the first seg- 

 ment be an exception ; that and the following segment have each 

 the front margin serrate ; the side-plates were not clearly made out 

 but appear to have some denticles larger than those on the general 

 surface. The pleon is longer than the anterior division of the body> 

 all of it denticulate except the telson, with several conspicuous 

 dorsal denticles and a few such subventral ; the fifth segment the 

 longest and the sixth the widest of the first six, the telson much longer 

 than the fifth segment, about two-thirds as long as the peduncle of 



