116 MR. F. E. BEDDARD ON ISOPODA COLLECTED _[Feb. 2, 
LEIOPUS, nov. gen. 
This genus is closely allied to the last, but differs in that the 
chelipeds and fossorial limbs have an exopodite. The chelipeds are 
extremely slender and delicate in their structure, and this, together 
with the characters of the abdominal appendages, serves to distinguish 
the genus from Apseudes. 
1. LEIOPUS LEPTODACTYLUS, 2. sp. 
This species attains to a length of 13 millim. 
The cephalothorax is prolonged in front into a long rostrum ; the 
ocular lobes are large and pointed anteriorly ; there is no trace of 
any optic structures; behind the ocular lobes are two long spiny 
processes, one on either side. The first free segment of the thorax is 
as wide as the cephalothorax; the following segments decrease in 
width, the first suddenly, the rest more gradually; the length of 
these segments increases up to the fourth; the fifth is of equal 
length with the fourth, the sixth rather shorter ; the first segment 
has well-developed spiny epimera; the last three segments of the 
thorax have also short spines upon the epimera, which are wanting 
in the intermediate segments; upon all the free thoracic segments, 
with the exception of the first, are a pair of long lateral spines like 
those of Typhlapseudes, but longer. On the ventral surface of both 
the thoracic and abdominal segments, with the exception of the last, 
is a median spine. The abdomen is much as in the last-described 
species. The outer flagellum of the antennules has twenty-seven 
joints, the inner only six. The antenne have a rudimentary exopodite. 
The chelipeds are very slender and delicate. The uropoda are as in 
Apseudes. 
Station 78; 1000 fathoms. 
Fam. TANAIDS. 
Genus Tanaris, Audouin & Milne-Edwards. 
1. TANAIS HIRSUTUS, D. sp. 
The extreme length of this species is 9 millim. 
The body is elongated, the anterior region is wider than that which 
follows; the last thoracic segment and the first three abdominal 
segments are again wider, after which the body narrows towards the 
termination. The cephalothorax has a short obtuse rostrum; the 
two first segments of the thorax are short and subequal, the third 
segment is narrower but longer; the two following segments increase 
progressively in length, the first is about twice the length of the 
preceding segment; the last thoracic segment is wider than the 
preceding, but shorter. The first three segments of the abdomen 
are wider as well as longer than the following ; the terminal segment 
ends in a blunt, rounded extremity. The antennules have a three- 
jointed peduncle anda two- or three-jointed palp ; the extremities of 
the joints of the peduncle are surrounded by a circle of fine delicate 
plumose hairs of great length. The antenne are similarly beset 
