30 
A. 0. WALKER, 
with the hind margin produced backwards in a spur; fifth and sixth with the 
hinder angles acute ; seventh small and subquadrate. 
The first two pleon-segnients have two long subdorsal teeth, as in the seventh 
segment; the lower margin of the first is narrowed, with the posterior angle obtuse ; 
the hind margin of the second is concave with the posterior angle acute ; the third 
segment is smooth with the posterior epimeral angle forming a short, blunt tooth and 
a longer curved tooth above it. 
First segment of the urus dorsally depressed, much longer than the remaining two 
united. 
Upper antennae: First joint with a strong distal tooth on the inner side reaching 
almost to the end of the second joint. 
First gnathopods with a chelate hand. 
Last three pairs of perseopods increasing in length successively, the last pair 
extending much beyond the ends of the uropods ; hind margin of the first joints 
smooth, more or less concave, and ending below in a subacute tooth. 
Telson reaching to the base of the peduncles of the third uropods, shorter than the 
width at the base, rather deeply notched. 
I. hodgsoni. (PI. 11, fig. 18.) 
I. hodgsoni, A. 0. Walker, Ann. and Mag. Nat. Hist. XVIII. (1906), p. 152. 
.Xh Coulman Island, 13 Jan., 1902, 100 fm., oneT 
The whole body is clothed with fine spine-like teetli directed backwards and 
arranged more or less in zones on the segments of the mesosome, pleon, and urus; the 
side-plates are also densely spinous, and appear to be a little deeper than the segments. 
The body is but little compressed laterally and is widest about the first and second 
segments of the mesosome. The antennse are rather short, subequal, and directed 
outwards, the basal joints of the upper being a mass of branching spines. The rostrum 
is almost straight and about as long as the rest of the head. Eyes round, darkish, and 
far apart. 
Inner plates of the maxillipeds folded and squarely truncate; outer broad and 
rounded. 
The gnathopods resemble those of I. ohesa, Rathke. 
Length 20 mm. 
The single specimen was only partially dissected. 
FAM. EUSIRILLE, G. O. Sars. 
Eusirus propinquus. 
mO^.C,,S3 & Eusirus propinquus, G. 0. Sars. 
W.Q., etc., various dates, very abundant. 
The only points of difference between this form and the type are as follows : The 
