CRUSTACEA OF THE MERGUI ARCHIPELAGO. 151 
broader in the middle than the ischium-joint, and it does not 
reach to the anterior margin of the merus-joint ; it is broadest in 
the middle and considerably narrower at the anterior extremity. 
The outer surface of the joints of the external maxillipeds is 
punctate; both the merus- and ischium-joints are marked with a 
longitudinal ridge on their outer surface, running close and 
parallel to the internal margins. The outer surface of the 
exopodite is convex. 
The abdomen of the male is rather narrow, and its lateral 
margins are nearly parallel, scarcely converging towards the ~ 
terminal end. The two basal joints do not occupy the whole 
width of the sternum between the bases of the legs of the last 
pair. The third and fourth joints are nearly three times as long 
as broad, and have the same length; the fifth and the sixth are 
as broad as the two preceding joints, and are successively a little 
longer; the terminal joint is rounded at the tip and its pos- 
terior margin is nearly as broad as its length. The female 
abdomen is much broader than that of the male and fringed, 
along the lateral margins, with hairs; the lateral margins of the 
joints are slightly arcuate. The outer surfaces of the sternum 
and of the abdomen are slightly punctate. 
The chelipedes of the largest specimen (2) are somewhat 
unequal, the left leg being slightly thelarger. The ischiopodites 
are armed with two or three minute acute tubercles on their 
anterior margin. The arms scarcely project beyond the lateral 
margins of the cephalothorax ; their outer surfaces are somewhat 
transversely rugose, and the margins are covered with some 
more or less acute granules. The upper surface of the wrist is 
covered with some minute granules, a few larger ones being found 
near the internal margin; the internal angle of the wrist is 
armed with a small acute tooth, and one or two smaller teeth are 
found immediately below it. The larger hand is scarcely twice 
as long as high, and the fingers are nearly as long as the palm; 
the latter has a tolerably convex outer surface and the under 
margin is also convex. The outer surface, which appears smooth 
to the naked eye, is marked below with a rather coarsely 
granulated or minutely denticulated longitudinal line, proceed- 
ing close and parallel to the under margin of the palm, to 
the tip of the immobile finger. One or two minute acute 
tubercles or granules are found on the outer surface near the 
middle of the distal margin of the palm, 7. e. a little below the 
