Malacostracous Crustaceans from Malaysia. 257 



Epigastric lobes very prominent ; no crest parallel to the 

 anterior margin of the front, general surface of the carapace 

 rather thickly punctate than granular. Upper surface of 

 meri of ambulatory legs with two granular eminences. There 

 is a minute epibranchial tooth as in P. Melanipi^e, behind 

 which the sides are obliquely rugose. 



In regard to the habitat from which it was taken, there is 

 no evidence to show that this species is essentially a cave- 

 dwelling one ; though its occurrence in a dark cave is very 

 interesting, and shows the possibility of such being the case. 

 The eyes in this individual are normal ; its colour is perhaps 

 paler than in the Thelphusidas generally (but cf. Potmion 

 bicristatum, de Man : " carapace lead-coloured, legs yellowish 

 mar m orate "). But a loss of colour of this nature is not 

 necessarily a permanent feature, and proves very little as to 

 the ways of the species as such. The possibility must always 

 be borne it) mind that a particular habitat, such as this, may 

 be one temporarily acquired by certain, possibly locally limited, 

 members of a species ; should this residence become per- 

 manent, a local race may be formed. But in this case, at 

 least, the evidence is very little, and not much can be deduced 

 from it in either direction. 



Dim.: Greatest length 12*25 millim., greatest breadth 14; 

 length of penultimate pair of legs 40, length of merus of 

 penult, pair 15. 



XII. Genus SESARMA, Say. 



19. Sesarma calypso, de Man. 



Sesarma (Parasesarma) calypso, de Man, Zoolog. Jahrb. Syst. Bd. ix. 



pp. 185-9, fig. 34 (1896). 

 Sesarma calypso, Lanchester, P. Z. S. Lond. (1900). 



Distr. Atjeh, Singapore. 



No. XXXVIII. Ilab. Bunral. 



A female. Superior border of hand raised to a strong; crest on 

 its inner side, against which the tour pectinated ridges abut. 

 Fingers with seven or eight of the characteristic " Treppen- 

 formig " tubercles. 



Dim. : Greatest length 16 millim., breadth (including ex- 

 ternal orbital angles) 20"5. 



20. Sesarma quadrata, Fabr. 



s, Fabr. Eut. Syst. Supp] 

 soma) qvadratvs, de Ha 



Distr. Malay Archipelago, Japan. 



Cancer quadratvs, Fabr. Eut. Syst. Suppl. p. 341 (1798) 

 Grapsus (Pachysoma) qvadratvs, de TIaan, Crust. Jap. p. l 222, pi. viii 

 tig. 3 (1839). 



