C4REGA.RI0US CRUSTACEA FROM CEYLON. 23 
latter in the specimen examined with accessory flagellum of three 
joints, the former having this appendage four-jointed. It is only 
to the female that Dana’s name tenuicornis would be applicable. 
Second antennae with gland-cone strongly produced, acute, 
fourth and fifth joints subequal, or sometimes the fifth the shorter > 
elongate in the male, the flagellum about eight-jointed, the first 
joint (especially in the male) much the longest, the end joints in 
that sex almost abruptly narrower. 
Upper lip with distal margin evenly rounded. 
Mandibles with slight quinquedentate cutting edge, secondary 
plate with four teeth on the left mandible, laminar and scarcely 
dentate on the right, spine row on left with four, on right with 
three spines, molar powerful with small lateral plate ; palp with 
third joint as long as second, neither densely fringed. 
First maxillae with five setae on broad apex of inner plate, palp 
with short first joint, the second long, carrying spine teeth and 
setules at the apex and overtopping the inner plate. In Dana’s 
figures of these maxillae for both sexes of M. incequistylis the first 
joint of the palp is two-thirds the length of the second. 
Second maxillae. Inner plate having a dozen setae on inner 
margin. Dana’s figures show only three. 
Maxillipeds narrow, both inner and outer plates carrying 
numerous spines, the outer plates much overtopped by the long 
second joint of the palp, its third joint distally widened and 
apically fringed, the fourth finger-like, the whole agreeing well 
with Dana’s figure. 
The first gnathopods of the male have the hind margin of the 
fourth joint densely furred, the fifth joint considerably longer 
than the sixth, beset on both margins and inner surface with 
numerous groups of spine-like setae, the sixth joint similarly but 
less densely setose, oblong, with the finger attached at the middle 
of the apex as in Dana’s figure of the male , its thin distal 
part resting on a slightly convex setulose palm margin. In the 
female there is less difference in length between fifth and sixth 
joints, and the finger is normally attached at the front of the apex, 
not at the middle as in Dana’s female . 
The second gnathopods in the male are very large, the fifth 
joint cup-like, with seven groups of setae about the hind margin, 
the sixth joint massive, oblong, not distally widened as in Melita 
palmata , with the outer surface smooth, but inner surface and 
hind margin densely setiferous, the strong finger half the length 
of the sixth joint over the distally rounded hind margin of which 
it closes, past a smooth tract of the inner surface to a strong 
recumbent ridge near the middle of that surface. In the female 
