62 NATURAL HISTORY OF KERGUELEN ISLAND. 



spines. The dactylus fits closely to the palmary margin. The propo- 

 dus in the second pair is in all respects similar, but stouter, beingfuUy half 

 as broad as long; the palmary margin is a little more oblique, not quite 

 as convex in outline, and the spines at the posterior angle are stouter. 

 The dactylus is so much curved that it does not fit closely the mid- 

 dle part of the palmary margin. The gnathopods of the female are sim- 

 ilar to those of the male, but much weaker and nearly equal in size, and 

 the setae of the posterior margins of the carpi and propodi are very much 

 longer. The propodus in each i^air is only a little longer than the car- 

 pus, about half as broad as long, and slightly narrowed proximally, and 

 the palmary margin is very nearly transverse, with its i)osterior angle 

 only very slightly rounded. 



The inferior margins of the first three segments of the pleon are 

 slightly arcuate and armed on the outside with a submarginal series of 

 short spines, but the edge is not serrate. The posterior margins of the 

 first and second segments are nearly straight and make nearly a right 

 angle, very slightly rounded, with the inferior margins, while the poste- 

 rior margin of the third segment is arcuate with the inferior angle 

 broadly rounded. The peduncles of the second uropods do not reach to 

 the tips of the peduncles of the first pair, and the outer rami in both 

 these pairs are much more slender and considerably shorter than the 

 inner, which reach nearly or quite to the tipsof the third pair. Theramiof 

 the posterior uropods are subequal, longerthan the peduncles, taper regu- 

 larly to acute points, and are armed along each margin with stout spines 

 and long setiform hairs, the latter principally upon the outer mar- 

 gins. The telson is about two thirds as broad as long, narrowi d dis- 

 tally, divided two-thirds of the way to the base, and armed with a 

 slender spine at the tip of each lobe, and often with one or two addi- 

 tional spines on each side. 



Length of the largest specimens, excluding the antennae, in the females 

 about O'"™ ; in the males a little less. 



The mouth-appendages agree very well with those of Atylus carinatus, 

 as figured by Kroyer (Voyages en Scandinavie, en Laponie, etc., pi. 11, 

 fig. 1), but the mandibular palpus is considerably stouter than repre- 

 sented in the figures referred to, and the second and third segments are 

 very nearly equal in length, the second segment somewhat stouter than 

 the third. 



Rocky beaches, Kerguelen Island. 



