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MUSEO NACIONAL DE BUENOS AIRES. 
Serolis polita Prerrer 
Serolis polita Pfeffer, Jahrbuch des Hamburgischen Wissens- 
chaftlichen Anstalten, 11, 1887, pp.S1-85, pl. 1, figs. 4-5.—— 
Richardson, Expédition Antarctique Francaise (1903-1905) 
commandée par le Dr. Jean Charcot, Crustacées, Isopodes, 
1906, p. 7, 1908, p. 5. 
Localité.—Sandwich du Sud. Lahille, 1910. Dix individus. 
The apex of the terminal abdominal segment is more acute than 
shown in Pfeffers figure. 
Serolis polaris sp. nov. 
Body broadly ovate, almost circular in outline, equally wide 
as-long, 22 mm. 22: mm. Color white. 
Head large, wider than long, 6 mm. : 4mm. The anterior margin 
is produced in a small median póoint, on either side of which 
there is a slight excavation for the reception of the basal articles 
of the antennae. On either side of these excavations the margin is 
produced forward, curving widely, and at the antero-lateral 
angles is drawn out in acute processes. Just behind the antero-la- 
teral processes, the lateral margins are constricted, so that the 
anterior portion of the head at this point is much narrower than 
the posterior portion. The eyes are placed in the posterior portion 
of the head near the lateral margins, and are reniform in shape. 
Betwen the eyes and a little anterior to them, are two rather flat. 
ronnded proceses, free at their posterior extremities from the 
surface of the head, situated one on either side of the median line. 
Close to the posterior border of the head are three flat processes, 
one median and one on either side, placed between the eyes and 
a little posterior to them; the median one is rounded posteriorly 
and not free, the lateral ones are angular, and free posteriorly 
from the dorsal surface of the head. The fisrst pair of antennae 
have the basal article large; the second article is about one and a 
half times as long as the first and is also somewhat dilated; the 
third article is narrow and is a little shorter than the second; the 
fourth article is less than half the length of the third; the flage- 
