CRUSTACEA OF THE MERGUI ARCHIPELAGO. 91 
running obliquely forwards from the posterior margin of the 
cephalothorax, and parallel to the postero-lateral margin, almost 
to the level of the last antero-lateral tooth. 
A little behind the frontal margin two slight transverse 
elevated lines are observed on the upper surface of the cephalo- 
thorax between the orbits; these epigastric ridges are separated 
from one another by a faint mesial frontal furrow, which is bifur- 
cated behind as usual. Two other transverse ridge-like eleva- 
tions are found on each antero-lateral region, the anterior of 
which is situated at the base of the third antero-lateral tooth ; 
whereas the posterior, parallel to the anterior, is found at the 
base of the fourth antero-lateral tooth. The anterior of these 
transverse ridges and the transverse epigastric ridges are united 
on each side by a ridge-like elevation which runs parallel to the 
upper orbital margin. ‘The cervical suture which separates the 
gastric from the cardiac region is very faintly marked. An 
impressed line proceeds close to and parallel to the posterior 
margin of the cephalothorax. The rest of the upper surface of 
the cephalothorax appears quite smooth and glabrous, slightly 
convex anteriorly and flattened posteriorly. 
In Eucrate affinis the endostome is more distinctly longitudi- 
nally ridged on each side than in LZ. crenata; but in the form 
of the epistome and of the anterior margin of the buccal cavity, 
both species resemble one another. The male abdomen is seven- 
jointed, scarcely narrower towards the base than the contiguous 
part of the sternum; the third joint is the most enlarged ; 
and the remaining terminal part is very narrow, the joints gra- 
dually increasing in length and decreasing in breadth, so that 
the terminal joint is the longest of all. I have only a female 
specimen of H. crenata before me, and I am therefore unable to 
decide whether both species agree with one another as regards. 
the form of the male abdomen; but the female abdomen presents 
precisely the same form in both species. 
The anterior legs are subequal, the right being in all the spe- 
cimens a little larger than the left; they have the same form 
and size both in the male and in the female. The anterior 
as well as the ambulatory legs are closcly similar to those of 
EL. crenata. 
The upper margin of the arms is armed witha strong tooth near 
its distal end, which is “separated distally by a transverse groove 
from a second, lower, transverse elevation,” as Haswell rightly 
