Henry Woodward — Fossil Crab from Mekran Coast. 307 



Neptunus Arabious, H. Woodw., sp. nov. See Text-figure (Fig. 1). 



Pliocene (?) : Mekran Coast. 



Description. — Carapace broader than long (5|^cm. by 3 cm.), 

 semicircular in front ; rostral border not prominently produced, 

 14 mm. wide, having a notch and a slight median depression in the 

 centre ; this divides two low, broad, undulated prominences, each 

 4 mm. wide, marking the position of the first or inner pair of 

 antennee ; these are separated by a notch (1 mm. deep) from the next 

 pair of double serrations, 3 mm. wide, covering the second or outer 

 pair of antennae ; they complete the rostrum and form the inner 

 orbital spine ; the orbits are large, oval, 7 mm. wide by 5 deep ; the 

 border marked by one fissure above and apparently none beneath ; 

 then follows the outer orbital spine (probably succeeded by seven 

 other more or less equal serrations), as indicated by dotted lines in 

 Fig. 1, ending with the strongly developed costal spine {l.s.), which 

 completes the latero-anterior angle of the carapace. The postero- 

 lateral border curves inwards and contracts rapidly from 5^ cm. 

 broad at the costal spine to 2 cm. behind the articulation of the fifth 

 pair of legs. The specimen was evidently a female ; therefore the 

 posterior border of the carapace is considerably wider than would be 

 that of a male of the same species. 



Gastric region 18 mm. broad, marked by a median longitudinal 

 depression in front, and a transverse, slightly raised line of minute 

 pustules across the centre, separating the epigastric and protogastric 

 from the mesogastric lobes ; the metagastric and the urogastric lobes 

 are continuous with one anothei", and form a slightly raised, shield- 

 like median space produced in front into a slender, spine-like ridge 

 4 mm. long, which terminates at the median epigastric furrow. The 

 hepatic region is not subdivided ; it is rather depressed anteriorly, 

 and is separated from the gastric region by a slight furrow and from 

 the branchial region by a curved, well-defined, raised ridge, which 

 extends from the gastric furrow to the extremity of the lateral or 

 costal spine. The cardiac region occupies a central position behind 

 the gastric region, being about 6 mm. broad in the centre, and is 

 subdivided anteriorly into two well-marked triangular lobes by 

 a median depression, ending in a pillar-like median lobe behind. 

 The branchial region is tumid, marked by a slight double swelling 

 next the gastric and cardiac border, where a somewhat deep furrow 

 is formed. 



The surface generally is finely granulated, with small patches of 

 <!oarser granules on the proto- and metagastric lobes and on the 

 adjacent branchial prominence, while a few minute, linear - wise 

 tubercles mark the mesogastric and hepatic lobes. 



The propodos of the fore-limb is 3 cm. long and 1 cm. broad, 

 the surface being covered with coarse, rounded granules and scored 

 longitudinally by two furrows which converge at the extremity of the 

 :fixed chela ; the moveable claw (dactylus) is not seen ; it must have 

 been 15 mm. in length. The carpus was 8mm. long : the meros 15 mm. 

 long by 7 mm. broad. The basal joints are concealed by matrix. 



The last or posterior pair of walking limbs in the genera 



