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This aberrant species discovered by A. Milne-Edwards has been never found, again 

 since 1873. 



The carapace is perfectly flattened, transversely oval, broader than long, 

 with the sides regularly convex and unarmed; the posterior margin is straight; the anterior 

 margin faintly convex, but beyond the latter the carapace slopes obliquely-forward and ends in a 

 short and broad, triangular, obtuse rostrum, not visible in a dorsal view of the carapace, as it 

 is nearly perpendicularly deflexed. The regions are defined by narrow but distinct sulci, the 

 course of which in my specimen nearly corresponds with the figure of Milne-Edwards : gastric 

 and cardiac regions are distinct, and the bordering sulci as well as the deep cervical groove are 

 situated in somewhat sunk and concave parts of the carapace, hepatical and branchial regions 

 are also indicated, and the latter area is again divided by a transverse bifurcating sulcus in 

 my specimen, parting from the end of the cervical groove, but simple and originating somewhat 

 more anteriorly in Milne-Edwards' figure. The lateral parts of the carapace are nearly perpen- 

 dicular. The whole carapace, also the sternum, save the abdomen, is covered 

 by a close, but very short, fur of a dark-brown colour; the hairs are somewhat 

 longer at the sides and here club-shaped; a group of such hairs is placed immediately anterior 

 to the bases of the chelipeds. The sternum is straight or somewhat concave transversely, but 

 much convex, especially posteriorly, in a longitudinal direction. The abdomen of the cf is 

 broadly triangular, but not occupying all the space between the posterior pair of legs; the 

 third segment is very short, almost linear; the next segment the broadest of all, with convex 

 lateral marorins, much loncrer laterally than in the median line, as the anterior marm'n is curved 

 rather abruptly backward in the middle (fig. ^c); the fifth segment is shorter than the next or 

 penultimate segment, which is the longest, and twice as long as the very short, broadly triangular 

 terminal joint, that is rounded at the tip. The general shape of the abdomen and the small 

 last joint have been perfectly recognized by Milne-Edwards. This terminal joint reaches forward 

 to the level of a line connecting the posterior part of the bases of the chelipeds, but there is 

 a rather great distance between the tip of the abdomen and the posterior margin of the 

 buccal cavity. 



The short eye-stalks are placed in shallow sockets, but there is no projecting external 

 orbital angle; the antennae arise below the 6ye-stalks, and the peduncle reaches only as far 

 forward as the eye; the antennulae are much stouter, with the basal joints close together and 

 partly overlapped by the somewhat projecting lateral parts of the rostrum, the two next peduncle- 

 joints of equal length, longer than the basal joint, and bent rectangularly to each other. 



The epistome is distinct, projecting in the median line both anteriorly and posteriorly. 

 Pterygostomial regions not longitudinally grooved or crested. Buccal cavern with the lateral 

 borders slightly diverging backward. External maxillipeds gaping, especially posteriorly, hairy 

 at outer surface, and > closely fringed at inner margins; ischium somewhat shorter than merus, 

 narrowing towards the base; both merus and ischium longer than broad, the latter not auriculated 

 anteriorly; palp very thick, but long, inserted near antero-internal angle of merus; exognath 

 partly concealed in normal position, slender, reaching nearly to anterior margin of merus (fig. 5<5). 



The chelipeds and walking legs are remarkably stout and shortened, 



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