MONOGRAPH OF THE LEUCOSIAD^. 299 



broad as it is long. The fingers differ from those in any other genus of the family, 

 with the exception of Nursilia, in their beautiful tenuity, their curvature, and then- 

 hooked points, which cross each other considerably when closed. 



This genus may be considered as bearing the same relation to Myra, as Leucosilia does 

 to Persephona ; and as Myra and Fersephona represent each other in the different hemi- 

 spheres, so may Myrodes and Leucosilia. 



Species unica, Myrodes eudactyltjs, mihi (Tab. XXXII. fig. 6). 

 Hab. ad insulas Philippinas. Muss. Brit., Bell. 



Carapace minutely and sparsely granulated, distinctly but slightly carinated ; hepatic 

 region with a small ridge, and a marguial tooth; cardiac region separated from the 

 branchial on each side by a slight depression ; the posterior teeth rather small, the middle 

 one the longest and placed a little higher than the others. Rostrum distinct, bifid, the 

 two tooth-Uke projections forming the covering of the antennary fossae, which are very 

 open. External foot-jaws with the palp evenly curved on the outer edge, but ^\'ithout the 

 dilatation which characterizes 3Iyra. Anterior legs short, the arm minutely granulated ; 

 hand swollen at the base, narrowed forwards, as broad as it is long ; the fingers slender, 

 elegantly curved, longer than the hand, armed with sharp teeth and hooked at the extre- 

 mity. Abdomen in the immatui-e female lanceolate, with a rather broad shallow carina. 



Length of carapace 9 in. 



This beautiful species was brought by Mr. Cuming from the Philippines, 



Genus Philtra, Leach. 



Char. Gen. — Testa orbicularis, depressa, inermis, fronte epistomate breviore. Fossa antennarice fere 

 transversales. Orblta supra aperta, trifissa. Pedipalpi externi caule exteriore dilatato. Pedes octo 

 posteriores tarso compresso, lamelloso. Abdomen Maris hastato-lanceolatum, — F(emin/E articulo 

 ultimo angusto valde producto. 



The character which has liitherto been considered as the essential one in this genus, 

 namely the extraordinary dilatation of the palp of the foot-jaws, varies greatly in degree 

 in the different species now known ; the outline in some being scarcely less than semi- 

 circvdar, wliilst in others it is not more curved than in Ilyra. This is another instance 

 of the importance of taking into account the whole organization of the animal, instead of 

 depending upon a single character of a single organ. The form of the carapace, the 

 absence of all armature, the character of the legs and other parts, are in the present in- 

 stance quite as important, and even more to be relied on, than the form of the palp of the 

 external foot-jaws. 



Philyra scabriuscula, Fabr. Testa depressa, granuloso-scabra, fronte epistomate multo 

 breviore ; brachiis tuberculatis, manibus ad marginem interiorem lineis duabus gra- 

 nulatis. 



Hab, in mari Indico. Muss. Brit., See. Linn., Bell. 

 Vide Edw. Hist. Nat. Crust, ii. p. 132. t. 20. f. 9, 10. 



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