224 



Abdomen of 9, like the sternum, naked on outer surface, but heavily fringed along the 

 margins, covering at base two-thirds of the interspace between the bases of the last pair of 

 leo-s seo-ments gradually increasing in length from first to sixth segment, terminal one semi- 

 elliptical, twice as long as preceding joint. 



The animal is of a uniform ivory-white colour in alcohol preservation, the toment is 

 greyish-white, the fingers are chestnut-brown. 

 Dimensions in mm. : 



Fronto-orbital distance . . . 4.75 

 Anterior margin of front . . 2.25 

 Breadth of carapace .... 11. 5 

 Length of carapace .... 7.7 



Scalopidia Stimpson. 



1858. Scalopidia Stimpson. Proc. Ac. Nat. Sc. Philadelphia, 1858, p. 95. 

 1881. Hypoplithahniis Richters. Abhandl. Senckenb. Gesellsch., Bd 12, p. 429. 

 1900. Scalopidia Alcock. Journ. As. Soc. Bengal, v. 69, prt 2, p. 325. 



Scalopidia belongs to those genera of the Rhizopinac in which the epistome is indistinct 

 and not well separated off by a prominent margin from the buccal cavity. The flattened, ante- 

 riorly not much deflexed carapace with its strongly marked regions, the flattened and sharply- 

 edged chelae, one of which is very much larger than the other, and the spider-like, posteriorly 

 spinous, walking legs render the only species of the genus very easily recognizable. 



I. Scalopidia spinosipes Stimpson. Pi. 14, Fig. 



5- J- 



Literature: Alcock, 1. c, p. 325. 



Laurie, Rep. Pearl Oyster Fish. Ceylon, prt 5, 1906, p. 424. 



Rathbun, K. Dansk. Vid. Selsk. Skr., 7. Raekke, Afd. 5, n" 4, 1910, p. 344, pi. 2, f. 2. 



Stat. 19. Labuan Tring, west coast of Lombok. Depth 18 — 27 m. i cT- 

 Stat. 71. Macassar. Depth up to 32 m. i (/ juv. 



Contrary to what is the usual case in the Rhizopinac the carapace is much flattened 

 and the front nearly horizontal, very short and not prominent. The general outline of the 

 animal re.sembles that of Xenophthalmodes in being semi-circular, with the lateral margins of 

 the carapace divergent backward, but, whereas in Xeiiophthalmodes the maximum breadth of 

 the carapace only very little exceeds its length, it is 1.35 times this length in the present 

 species. The surface is bare and, on close examination, it proves to be everywhere punctate, 

 and the various regions are defined by broad, shallow depressions ^). These are best developed 

 around the cardiac area, which is of a rhombic shape and presents an indistinct, broad, 

 but low, transverse ridge; there are further two inner branchial lobes; branchial and 

 hepatic regions are separated by a broad sulcus, which gives off a branch passing anteriorly 

 to a large depression behind the orbit; a median groove passes from the front backward and 



l) Alcock states: "the regions are distinctly mapped out by fine grooves", but these grooves are not so clearly marked in 

 my specimens. 



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