CRUSTACEA OF THE MERGUI ARCHIPELAGO. 147 
arm is also tuberculiferous, and armed at its distal end with a 
short acute spine (as in J. messor). The outer surface of the 
wrist is transversely rugose and covered with some small, more 
or less acute tubercles, also at the internal angle. The hands 
(Pl. X. fig. 2) are a little more elongate (less high) than those 
of WU. messor, and differ at first sight by their outer surface 
being never smooth. The proximal half of the outer surface 
is covered with many short, oblique, elevated lines, which 
gradually change towards the fingers into minute granules. As 
in MM. messor, an elevated line, nearly parallel to the rounded 
and rugose under margin of the hand, proceeds towards the base 
of the immobile finger. The rounded upper margin is covered 
with numerous small acute tubercles, and the convex inner sur- 
face of the hand is granular. The fingers have slightly excavated 
horny tips, and their somewhat punctate external surface is 
smooth, but slightly granular at the base; the thumb appears 
to be somewhat more slender than that of JL. messor, and 
its upper surface also is covered with small acute tubercles, which, 
however, are more numerous and somewhat larger than in that 
species. The under surface of the index is also somewhat 
tubercular. 
The ambulatory legs present a striking resemblance to those 
of MW. pictus, figured in the‘ Nouvelles Archives.’ In ML. messor, 
on the contrary, the penultimate joints (or propodites) are com- 
paratively much less elongate. 
M. latifrons, White, is probably identical with I. maculatus, 
and in that case has the priority. 
Dimensions :— 
(ox SZ 
millim, millim. 
Distance between the external orbital angles. 29 27 
Length of the carapace (the front included) . 225 213 
Breadth of the front (measured between the 
SHE ePCUUMMCLOS)) Lo silat cele Oise aha shee sits 193 18% 
Length of the propodites of the third pair of 
ambulatory legs, measured in the middle of 
(ili ONE, Meee Eee eae ee any Ee Ws als} 
Metopograpsus maculatus has hitherto been recorded from 
Batavia (Milne-Hdwards) ; and specimens of this species in the 
Leyden Museum were collected on the coast of Java. 
10* 
