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From the Journal, Asiatic Society of Bengal, Vol. LXIV, Part II, No. 2, 



1895. 



Description of a New Species of Oxyrhynch Grab of the Genus Parthenope. 



— By A. Alcock, M. B., C. M. Z. S., Superintendent of 



the Indian Museum. 



[Read 3rd July.] 



The species here described is a true Parthenope as delimited by 



Miers, Journ. Linn. Soc, Zool., Vol. XIV. 1879, p. 668. 



Parthenope investigatoris, n. sp. 



Carapace almost equilaterally triangular, the sides very slightly 

 curved: its surface is deeply eroded and rugose as in P. horrid a and 

 spinosissima, but is almost devoid of the sharp tubercles found in 

 those species: the antero-lateral borders are slightly crenulate : the 

 produced postero-lateral angle is rounded and nearly smooth : the 



posterior border bears five small eroded lobules a very small one 



in the middle line, with two larger ones on either side with 



intervening granules. The gastric region is enormously inflated 

 as in P. spinosissima, and descends almost vertically to the vertically 

 deflexed rostrum, the latter being fused with the interantennulary 

 tooth. The hepatic regions are rounded laterally, not strongly angulat- 

 ed as they are in P. horrida and spinosissima. The external maxillipeds, 

 when closed, have the inner edges in the closest contact throughout. 



The chelipeds have the merits very short and squat its breadth 



about two-thirds of its length with two compressed teeth on its 



short anterior (inner) border, a few blunt teeth followed by a blunt 

 lobe on its posterior (outer) border, a strong tubercle in the middle of 

 its upper surface, and numerous pearly tubercles and nodules on its 

 lower surface : the carpus is granular and pustular : the hand has five 

 sharp almost equal sized teeth on the lower border (two of them being 

 on the immobile finger), several large nodules on the outer surface, and 

 several large unequal sized spiny lobules on its inner surface: the 

 mobile finger is spiny. 



The ambulatory legs are compressed : the merus is compressed- 

 trigonal, with the edges, especially the anterior edge, spiny : the carpus 

 is indistinctly nodular: the propodus is also slightly nodular, with a few 

 spinules on its posterior margin : the dactylus is closety covered with 

 spinules up to its tip. 



The sternum, in the female, is excavated between the chelipeds. 



The abdominal terga, in the female, are raised into strong quadran- 

 gular convexities down the middle line, and on either side near the edge. 

 Loc. — Pedro Shoal, ? depth ; and Laccadives, 28 fms. 



Length of carapace of largest specimen (female) 45 millim., great- 

 est breadth 61 millim. 



138 



