RICHARDSON : ISOPODES DU SANDWICH DU SUD. 397 
llum is composed of eleven articles and extens a little beyond 
the peduncle of the second antennae and almost to the post-late- 
ral angle of the first thoracic segment. The second antennae have 
the first article of the peduncle short and not visible in a dorsal 
view; the second article is produced forward and is geniculate 
with the third article, which is a litle shorter than the second; 
the fourth; article is twice as long as the third; the fifth article 
1s more slender and a little longer than the fourth; the flagellam, 
composed of twenty-one articles, extends to the post-lateral angle 
of the second thoracic segment. 
Fig. 1.— Serolis polaris. Xx. 
The head is deeply set in the first segment of the thorax. The 
lateral portions of this segmsnt are broad and are separated into 
two parts by a curving transverse ridge; the post-lateral angles 
are acutely produced. The five following segments also have the 
posts lateral angles acutely produced backward, those of the sixth 
segment extendig tho the post-lateral angles of the terminal ab- 
dominal segment. The epimera of the second, third, fourth and 
fifth segments are marked by a suture. On the posterior margin 
of the second, third, fourth fifth and sixth segments, just within 
the epimeral suture is an angular prominence on either side. All 
