Report on the zoological collections made in the Indo-Pacific Ocean ...

276 COLLECTIONS FKOM MELANESIA.he does not notice that the outer margin of the smaller chelipedeis armed with a series of minute spinules, which are often concealedby the pubescence. The smaller chelipede in the adult male andboth chelipedes in the smaller specimens have the anterior marginof the wrist armed with two teeth, and in the smaller specimens(which j-et I cannot think belong to a distinct species) the frontaland upper orbital margins are very minutely spinnlose. There isdeveloped in both chelipedes a more or less distinct longitudinalmedian ridge on the upper surface of the wrist and palm, and theouter margin of the hand in both is armed with a series of smallspinules, so that these specimens in many points resemble Porcellanaornata, Stimpson, from Hong Kong.20. Porcellana quadrilohata. (Plate XXX. fig. D.)In the single male from Port Denison, 4 fms., thus designated, thecarapace is shaped nearly as in Porcellanella triloha, that is, it is muchlonger than broad, with the sides very slightly arcuated. The uppersurface, when viewed under a lens of sufficient power, is seen to bemarked with numerous rather closely-set transverse strife. The interantcnnularyportion of the front, which in P. triloba is entire, is in P.quadrilohata divided by a median triangular notch (which, however,is not so deep as the lateral notches), hence the front appears 4-lobed.The lobes are triangular and acute ; on the inner margin of each ofthe outer lobes is a small spiuule, and the inner margins of each ofthe inner lobes is minutely serrated. There is a very small tooth orspine at the outer orbital angle, and posterior to this the sides of thecarapace are armed with five spines, tlie three posterior of which areplaced near to one another and separated by a somewhat wider intervalfrom the preceding tooth. On the inferior surface of the carapace,below the inferior orbital margin, there is a strong spine. Theeyes are set on very short pedicels, and are nearly concealed withinthe orbits. The joints of the peduncles of the antennce are short (theflagella wanting in the single specimen examined). There is a spineat the distal end of the basus-joint of the outer maxillipedes ; theischium-joint is somewhat dilated, scarcely at all emarginate at itsdistal end, where it is articulated with the merus, which is excavatedat its distal extremity ; the three following joints are moderatelyrobust. The chelipedes are proportionately rather slender and elongated; the merus or arm is short, its inner margin somewhat cristiform,and terminating in a thin subacute lobe ; there is a spine alsoon the under surface of the merus ; the wrist is about as long as thepalm, and is armed with three spines or teeth on its inner margin :the hand is slightly contorted : the surface both of hand and wristfinely striated ; the fingers are rather shorter than the palm, meetalong their inner edges when closed and cross at the tips, which areincurved ; at the bases of the inner margins of the fingers is a patchof hair ; the lower margin of the lower finger is armed with a seriesof small spinules. The ambulatory legs are rather slender ; there area few short stiff sdce, or mobile spines, at the distal end of the