688 
Proceedings of the Royal Society 
Ampelisca compacta , Norman, n. sp. 
Pleon not keeled, a very slight depression across the middle of the 
fifth segment, hind margin of that segment with a spine-like point, 
but not largely developed nor upturned. Upper antennae exceeding 
the length of the peduncle of the lower by about a length equal to the 
last joint of that peduncle, flagellum consisting of ten articulations; 
lower antennae much longer than the upper, and having the two last 
joints of the peduncle subequal to each other. Eyes apparently 
altogether absent. First two pairs of pereiopods with the last joint 
about equal to the two preceding combined. The last pereiopods 
have the basos with the posterior lobe well developed reaching to the 
end of the ischium, the lower margin truncate and slightly concave ; 
ischium equal in length to the two following joints combined, meros 
short, carpus rather longer, manus not quite equal to the two 
preceding joints combined, dactylus half the length of manus; the 
lower joints are all flattened but simple (not produced downwards as 
in A. Icevigata). First two pairs of uropods of the same length, 
subequal in length to the deeply cleft telson, and reaching to about 
one-fourth the length of the sparingly-ciliated branches of the last 
uropods ; the outer margin of the outer branch of the second uropods 
bears two spines, and under a high power of the microscope is seen 
to be minutely crenulated. The entire animal has a rounded compact 
appearance, and is about 8 millemetres long. 
A single specimen. Station 7 ; 530 fathoms. 
Halirages elega?is, Norman, n. sp. 
Pereion and pleon not carinated, two last segments of the former 
and two first of the latter bearing a single central dorsal spine-like 
process, which is small on the first of these segments (and sometimes 
absent), but increases in size on each of the succeeding segments ; 
fourth segment of pleon with a deep transverse sulcus. Lower and 
front angles of the head produced into an acute spine-like process ; 
epimera of first and second pereion segments with serrated margins, 
the first also produced forwards into a sharp angle, rounded behind, 
the second rounded before and behind. Lower margin of the pleon 
segments not serrated, bearing rows of rather distant seta-like spines 
