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the lobes are separated by a broad, triangular notch and, in anterior view, much sloping 

 dorsally and backvvard towards the lateral angles, where a slight prominence is found. The 

 upper margin of the orbit is obhquely sloping backward, somewhat convex (iig. i a), not 

 notched as in the preceding species; the extern al orbital angle projects in the 

 form of a small, curved tooth, \v i t h the. tip curved forward, a little way 

 behind it an exact ly similar tooth is found and at a smaller distance than 

 that bet ween the first and the second a third much smaller tooth is o b- 

 served. In the adult cf, that is smaller than the Q, these lateral teeth are proportionately 

 strenger than in the adult 9 (compare figs i and i a). The lateral margins of the carapace 

 are nowhere sharpened, not even in the neighbourhood of the teeth; their course is convex, 

 but the breadth of the carapace between the external orbital angles is exactly the same as 

 that at the level of the penultimate pair of legs. 



The antennae are strong, the flagella com.posed of about 13 — 17 joints; in the cf each 

 of these joints, except several of the distal ones, is very little hairy, in the 9 they bear a 

 wreath of very long setae. The last joint of the antennular peduncle is thick, not increasing 

 much in size towards the distal end. The epistome is pushed far backward, especially in its 

 central portion, the free margin nearly vertical ; lateral margins of buccal cavern parallel. 

 External maxillipeds characteristically elongate, the long axis of the 

 ischium nearly twice its breadth (tig. i ó), antero-internal angle of ischium projecting, 

 m e r u s r o u g h 1 y e 1 1 i p t i c a 1 , much s h o r t e r and n a r r o w e r than ischium, 1 a te r a 1 

 and anterior margin form ing a regular curve without i n t e r r u p t i o n , carpus 

 very broad and implanted at distal extremity of merus ; exognath slender, half as broad 

 as ischium. 



Chelipeds short, of equal size in the cf. Outer border of meropodite finely serrate, 

 outer surface granulate,' inner border with one spine, two proximal ones being placed on the 

 inner margin of the ischiopodite, upper border with four smaller spines, increasing in size 

 distally. Wrist finely granular at upper surface, inner angle with a sharp tooth, directed forward, 

 beneath this tooth and placed farther backward a similar, but smaller tooth is observed, antero- 

 external border of wrist with two sharp teeth. Chela (fig. i c) rather high in the i:? , with 

 scattered granules at outer surface, upper and under border rounded; fixed finger high at the 

 base,- greatly compressed and keeled below, with four wing-like expansions, separated by curved 

 furrows, at the inner margin, the last crenulation being as large as the faintly curved tip of 

 the finger ; movable finger greatly curved in its distal half, not compressed, and with two or 

 three faint crenulations at the inner margin. 



The walking legs are much elongate, so that the specific name aranca seems appropriate ; 

 penultimate pair more than three times the length of the carapace. Meropodites slender, not 

 narrowing distally, more than five times as long as broad, and spinous along anterior 

 margins. In all the legs this margin ends in a spine; besides, in the first pair of legs there 

 are two spines on the distal half of the margin, in the second pair three or four spines are 

 placed at equal distances, in the third a group of three very small spines are placed near one 

 another in the proximal half and two much larger ones in the distal portion, the last pair 



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