184 ZOOLOGISCHE MEDEDEELINGEN — DEEL ITI. 
always more than half the distance between the external orbital angles 
(in the 5 specimens measured this breadth is respectively 51.6, 52.4, 
51.2, 52.5 and 53.2°/, of the said distance). 
The postfrontal lobes are well marked, rounded at the anterior mar- 
gin, the median lobes separated from each other by a deep and broad 
furrow, and separated from the outer ones by a much narrower and 
shorter furrow; the latter lobes are only */, as broad as the median ones 
and bear a distinct posterior lobe. Owing to the comparative narrowness 
of the front the orbits seem to be larger than in Ses. taeniolata. The 
lateral margins of the front are somewhat concave, the fore margin has 
a deep and broad median sinus, of exactly the same appearance as in 
Ses. taeniolata, and the two lateral lobes, laterally separated off from the 
anterior edges of the front by a slight but distinct excavation, are also 
alike in both species. 
The upper orbital border is oblique, ending in an acute external angle 
with convex lateral margin; this orbital angle is separated by a deep 
incision from the subrectangular but acuminate epibranchial tooth, the 
lateral margin of which is about as long as that of the external orbital 
angle, but perfectly straight and converging with that of the other side; 
from the base of the epibranchial teeth the lateral margins of the cara- 
pace converge distally. In Ses. taeniolata the external orbital angle is 
perfectly equally shaped to that of Ses. palawanensis, but the incision 
between this angle and the epibranchial tooth is somewhat broader, and 
the epibranchial tooth itself is acute, not subrectangular, with the tip 
much curved upward, and there is a very small second epibranchial tooth 
which is not found in Ses. palawanensis. 
The chelipeds are in my single specimen (Q) wholly equal to each 
other; arm and wrist are similar to those of Ses. taeniolata, with a large, 
acute and curved tooth at the subdistal end of the superior border of the 
arm, and a dentate inner angle of the wrist, the upper surface of which 
seems somewhat less rugose and furnished with fewer granules in Ses. 
palawanensis than in White's species. 
The palm is (in the Q) shorter than the fingers; the outer surface is 
covered with granules, which are largest and most depressed towards the 
superior border, tending to form an obliquely longitudinal row of 3—4 
granules in the middle of the outer surface, and becoming more crowded 
and sharper towards the under border; they do not extend on to the 
under border of the immobile finger. Near the upper border of 
the palm there is a continuous row of small granules, 
which, as has been observed also by Miss Rathbun, runs along the whole 
superior border, from the articulation with the wrist to the somewhat 
