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also broader than carpus, but this is not the case in my specimens at hand; dactylus very 

 long, as already stated by de Haan, but not figured by him ; exognath narrowing distally, 

 at its base (at least in my specimens) nearly as wide as the basal part of the ischium. 



4" Chelipeds unequal, the right chela being higher (height of palm nearly equalling its length) 

 and more inflated than the left ; the fingers of this chela are not so short as figured by 

 DE Haan ^) and the movable finger exhibits one or two truncate teeth near the base of 

 the inner margin. 



5" Walking legs short : meropodites of second and third (last) pair twice as long as broad, 

 widening distally, in the second pair longer than in the third, superior margin tomentose 

 in cf, glabrous in 9; propodites nearly semi-circular, with the posterior margin, like that 

 of carpopodite, long-hairy ; dactyli short, thick, straight, hairy at inner margin ; in the last 

 pair Stebbing figures the dactyli as being constricted in the distal part, but I observed 

 nothing of this kind in my specimens. 



6" In the first sternal segment of the cf there are two broad, sinuous grooves, 

 parting from the anterior portion of the deep trench, into which the 

 abdomen fits, for the reception of the distal part of the long, outwardly- 

 curving first abdominal appendages. I find these transverse grooves in the 

 "Siboga" specimens as well as in that of de Haan; as they are, however, shallow and filled 

 with hairs, they may be easily overlooked. That de Man has made no mention of them 

 may possibly be explained by the gradual disappearance of the grooves in such large 

 examples as examined by him. On account of the transverse grooves being present in 

 Hexapus, the difference between this genus and Lambdophalhis becomes only gradual, and 

 I have no doubt that Lambdophalhis anfrachis Rathbun ") is wholly identical with Hexapus 

 sexifes, to which species the former showed, as Miss Rathbun herself admitted, "a suspicious 

 resemblance"; also in many other respects (lobe-like projection of postero-lateral margins 

 of carapace, slight mobility of eye-stalks, shape of external maxillipeds, buccal cavity, chelipeds, 

 walking legs and abdomen) there is a complete agreement between both species. 



7° The abdomen of the cf is very narrow as compared to the broad sternum ; the two first 

 segments (fig. id) are very short, linear; the third, fourth and fifth segment are completely 

 coalesced^) and together form a continuous plate, as broad at the base as long; the 

 penultimate segment is subquadrate, large, longer than the terminal one; the latter is 

 subtriangular, thickly fringed with rather long, feathered hairs, which also are implanted on 

 the suture between this segment and the preceding. The abdomen of the 9 is only slightly 

 broader in the middle than that of the cf and all the segments are separated. 



This species has been recorded from Japan, New Caledonia, Amboyna, and (though 



doubtfully, Stebbing) from the Cape. In the Gulf of Siam a whole series of specimens of 



Lambdophallus anfradus were obtained, but, though Miss Rathbun records several ovigerous 



9, the dimensions of a single cf only, of moderate size, are given. 



i) L. c, pi. II, f. 6. 



2) K. Dansk. Vid. Selsk. Skv., 7. Raekke, Afd. 5, nO 4, 1910, p. 348, textfig. 36. 



3) In DE Haan's specimen, just as has been depicted by this author, these segments are not fused. 



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