's RIJKS MUSEUM VAN NATUURLIJKE HISTORIE —LEIDEN. 185 



of obtuse tubercles, parallel with the distinctly converging sides of the 

 carapace. The upper orbital border is elegantly curved and ends in a 

 sharp, obliquely pointing tooth, which reaches as far forward as the 

 upper orbital margin. The following lateral teeth of the carapace are 

 much smaller, all directed obliquely forward. The eyes do not at all 

 reach the external orbital angle. Front narrow, bilobed at the free margin. 

 Grooves on the carapace all distinct. 



The chelipeds of the male are rather long and are everywhere smooth, 

 also on the palm. The fingers are very short, their length being about 

 one half of the length of the palm (without index), clothed with hairs 

 at the inside. The immobile finger has a large tooth at about the middle 

 of its length, the dactylus bears a smaller, but well-defined tooth near 

 the base. As in the preceding' species there seems to be a spine at the 

 anterior margin of the meropodites of the last pair of legs, near the 

 distal end, though Stimpson does not particularly make mention of it. 



This small species, with a carapace-breadth of 13 mm. (measured 

 between the tips of the outer orbital angles) and a length of about 8 mm., 

 has been found originally at Hongkong ; it appears to be not uncommon 

 in the Gulf of Siam. The Museum does not possess it. 



M. quadratus A. Milne-Edwards (PI. VIII, Fig. 10). 



1873. M. quadratus A. Milne-Edwards. Nouv. Arch. Mus. d'Hist. nat. 

 Paris, t. 9, p. 280, pi. 12 f. 6 (New Caledonia). 



The species at first sight is very much like M. erato, but, except for 

 the differently shaped inferior orbital margin in the male, it is distin- 

 guished by the much stronger curve of the superior orbital border, by 

 the outer orbital angle being more strongly pronounced and reaching 

 farther outward than the next lateral tooth of the carapace, and finally 

 by the lesser hairiness of the walking legs and the slenderness of their 

 meropodites. 



Nearly the whole surface of the carapace is granulated; the granules 

 are most crowded on the branchial regions, on the hepatical regions they 

 are more scattered and extend towards the mesogastric area. The ridge 

 in the broad, not constricted, nearly vertically deflexed front is rather 

 deep, especially between the transverse epigastric ridges, immediately 

 behind which it bifurcates. As Milne-Edwards remarked, the carapace is 

 covered by short hairs, somewhat more crowded on the lateral regions. 

 The outer orbital angle projects obliquely forward, its tip is pointed and 

 its hinder margin presents some small dentations. The first antero-lateral 

 tooth is slightly shorter, its anterior margin is directed less forward than 



