1900.] PROM SINGAPORE AND MALACCA. 727 



20. Lambrus pelagicus Riipp. 



Lambrus pelagicus, Riipp. Beschreib. 24 Krabben, p. 15, pi. iv. 

 f. 1 (1830) ; M.-Edw. Hist. Nat. Crust, t. i. p. 355 (1834). 



? Lambrus rumphii, Bleeker, Recti, sur Crust, de l'lnde Archipel, 

 Batavia, p. 18 (1856). 



Lambrus aflinis, A. M.-Edw. Nouv. Arch. Mus. t. viii. p. 261, 

 pi. xiv. f. 4 (1872) ; Henderson, Trans. Linn. Soc, Zool. vol. v. 

 p. 350 (1893). 



Lambrus pelagicus, de Man, Decap. u. Stom. von Malakka, 

 Borneo, etc., Zoolog. Jahrb. Bd. viii. p. 494 (1895). 



Hah. Singapore ; from sandy shore at low-water. One male. 



Dr. deMan, by a comparison with Riippell's original specimens, 

 has shown that the Lambrus affinis of A. M.-Edw. is identical 

 with Riippell's L. pelagicus ; and possibly also with L. rumphii 

 Bleeker. 



Dim. 17x16. 



21. Lambrus tumib-us, sp. nov. (Plate XLIV. fig. 2.) 



Hab. Malacca ; 2-6 fms. ; muddy bottom. A male and a 

 female. 



Carapace a very little broader than long, general surface smooth ; 

 gastro-cardiac and branchial regions strongly tumid, separated by 

 two wide and deep depressions. A median carina, branched 

 anteriorly towards the base of the rostrum and enclosing there a 

 concave triangular space ; a low tubercle at the point of bifur- 

 cation, a second stronger tubercle in the centre of the cardiac 

 region, and a third, as strong, half-way between the second and the 

 first. Behind the second the carina shelves rapidly to a slightly 

 upturned median spine on the posterior margin; the shelving 

 portion bears a minute tubercle. Antero-lateral margins, behind 

 the narrow hepatic notch, with eight flattened, obscurely laciniated, 

 triangular spines, which increase in size from before backwards 

 to the 7th, while the eighth becomes suddenly twice as large as the 

 7th, quite thin and laminate. Between this and the median 

 posterior tooth are three teeth : first, an outwardly directed tooth, 

 as strong as the eighth antero-lateral, carinate above, the carina 

 granular and extending on to the tumid branchial region, where it 

 becomes tubercular ; from the base of this tooth, on the postero- 

 lateral margin springs a shorter flattened tooth, not carinate, and 

 bearing in turn at its base a minute tooth ; and at a little distance 

 on the external angle of the posterior margin, a tooth equal in size 

 to the median posterior. The bed of the furrow separating the 

 gastro-cardiac and branchial regions has in it four or five relatively 

 deep holes, having the appearance of pin-prick s. Rostrum conical, 

 acute, with a single, obscure tooth on either side of the base, just 

 above the eye. The suborbital tooth is very strong and carinated 

 below ; a low granulated carina extends from the base of this 

 tooth to the base of the chelipedes : pterygostomian regions 

 otherwise smooth, under a covering of rather dense hair which 



