194 STALK-EYED CRUSTACEA. 
The epipods themselves consist of a thickened basal segment which bears a 
thinner flabelliform terminal segment. 
Length, 94 mm.; rostrum, 9 mm. ; carapace, including rostrum, 33 mm. 
Station 3413. 1360 fathoms. 1 fem. 
ARISTASUS Dvvernoy. 
Ann. Sci. Nat. 2° Sér., XV. 104, 1841 [Avisteus]. 
Aristeus occidentalis Fax. 
Plate XLIX., Fig. 2-2. 
Bull. Mus. Comp. Zo6l., XXIV. 215, 1893. 
Rostrum much longer than the rest of the carapace, armed with two 
teeth near the proximal end of the upper margin, its distal two thirds 
curved upward. Anterior half of the carapace with a median dorsal carina, 
armed with one tooth on the anterior part of the gastric region. Cardiaco- 
branchial groove distinct. Antero-lateral margin armed with a sharp tooth at 
the lower orbital angle. Below this there is a submarginal spine on a level 
with the second antennew. Fourth abdominal segment carinated on its distal 
half, and armed with a small posterior tooth. Fifth abdominal segment cari- 
nated on the distal two thirds, and produced to a tooth on the posterior 
margin. Sixth abdominal segment carinated throughout its whole length, 
and armed with a posterior tooth. Margin of telson excavated near the 
base. 
External spine (stylocerite) of the basal segment of the antennule a little 
longer than the segment, closely applied to the external margin of the seg- 
ment, but not fused with it. Prosartema wanting. 
Antennal scale broad, membranaceous, reaching beyond the superior an- 
tennular flagellum, and a little beyond the middle of the rostrum ; antennal 
peduncle unarmed. Terminal segment of mandibular palpus not bilobed. 
Exopod of second maxilliped equal in length to the whole endopod. Exopod 
of third maxilliped equal in length to the ischium and merus together. 
There are no exopods on any of the legs. Carpus and propodite of the legs 
ornamented with a longitudinal series of small pits defined (in alcohol) by red 
pigment. External branches of abdominal appendages very long, diminish- 
nopeneus as described by Smith), there are none on the third maxillipeds or any of the legs, while in H. thetis 
rudimentary podobranchiz are found on the third maxillipeds and the first, second, and third pairs of legs. 
