SERGESTES INOUS. 209 
of antennx ; the eyes are black and small, not exceeding the eye-stalks in 
diameter. The first segment of the antennular peduncle is somewhat shorter 
than the second; the second and third segments are about equal in length. 
The second segment of the antenna is unarmed; the scale is broad to the 
tip, and reaches a little way beyond the proximal end of the third segment 
of the antennular peduncle. The second pair of maxillipeds are robust and 
reach forward to the distal end of the proximal segment of the antennular 
peduncle. The third maxillipeds and the third pair of legs are the longest 
of the appendages; they are subequal in length, reaching much beyond the 
distal end of the antennular peduncle. The second and third pairs of legs 
are furnished with a minute terminal chela, the fingers of which are tipped 
with a brush of sete. There is a tuft of sete at the distal end of the inferior 
margin of the carpus, corresponding to a similar tuft near the proximal end 
of the propodite. The penultimate pair of legs are about as long as the 
carapace; they are flattened and furnished with long cilia, as is customary 
in this genus. The posterior pair of legs is wanting in the only specimen 
obtained. 
The abdominal appendages are very long, diminishing in length poste- 
riorly. The external branch of the caudal fin or swimmeret appears to be 
without an external spine, but an angle in the outer margin, one quarter of 
the way from the distal end, marks the position of the spine commonly found 
on this appendage. 
Length, 113 mm. ; carapace, 34.5 mm. 
Station 3380. 899 fathoms. 1 female. 
The branchial organs are arranged as follows : — 
Somite _ Vil. VIII. Tee Xs XI. JOG OST0y 21% 
Pleurobranchie 0 O+2 1427 147 1442 iz 2 0=7+41 
Arthrobranchie 0 0 0 0 0 0 0 0 =—0 
Podobranchie O 1 0 0 0 0 0 0 =1 
Epipods af al 0 0 0 0 0 0 = (2) 
8447+ @) 
In the above formula the letter 7 stands for the simple lamella which 
represents the second pleurobranchia on the eighth to the eleventh somites. 
The pleurobranchiw of the tenth and eleventh, and the anterior pleuro- 
branchia of the twelfth, somite are of about an equal size, and are the 
largest of all the gills. The posterior pleurobranchia of the twelfth somite 
(Plate LI., Fig. 2%, pi.’), though smaller than the anterior, is perfect in form 
27 
