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exactly one-third in Laurie's specimens of L. integrd). This fact is in contradiction te Borradaile's 

 statement, that the front in Lanchester's species is narrower than in L. integra. 



The external maxillipeds agree with Miers' figure, the antero-external angle of the merus 

 is rounded and not prominent. 



The chelipeds are equal in my specimen ; the meropodite is not armed at the upper 

 border ; the wrist is granulate above, produced at the inner angle ; the outer surface of the 

 palm is likewise finely granulate; the fingers are as long as the palm, not compressed, gaping, 

 strongly curved towards the tips, finely crenulate at inner margins, and of a light sepia-brown 

 in their distal portion. 



The walking legs are slender, the penultimate pair measuring more than 2^3 times the 

 length of the carapace ; the propodites elongate, as long as the dactyli ; the latter are of the 

 usual shape in Litocheira, not spined near the tip. De Man says that the dactyli of the last 

 legs are slightly curved, upward, "both in this species and in C. setosus^ the same way as in 

 the genus Pilumnoplax'^ and this is indeed observed to be the case, if the dactylus is viewed 

 from behind. 



Though the negative evidence of my specimen being not identical with L. integra is, 

 in my opinion, beyond question, there is, it must be admitted, none the more probability that 

 my identificating the specimen with L. siióintegra is right, my only argument being that the 

 animal apparently agrees with that of de Man, and Lanchester expressly states that specimens 

 from the very locality (Mergui Arch.) whence de Man got his material, agree with his (from 

 Singapore or Malacca). 



Dimensions in mm. 



Breadth of fronto-orbital border . . 3.75 



Breadth of front 1.98 



Grcatest breadth of carapace . . . 4.5 



Length of carapace 3.45 



Libystes A. Milne-Edwards. 



1867. Libystes A. Milne-Edwards. Ann. Soc. Ent. France (4), t. 7, p. 285. 



1868. Libystes A. Milne-Edwards. Nouv. Arch. Mus. Paris, t. 4, p. 83. 



This genus, together with the following, is nearly related to Carcinoplax, on account 

 of the carapace being transversely-oval and the fronto-orbital border being far less than the 

 greatest width. On the other hand there is even a greater resemblance to the Portunidae, as 

 will be explained in discussing the genus Catoptrus. 



The differences enumerated by Alcock between Libystes and Catoptrus are of no special 

 importance; the type species of each genus indeed differ widely by the carapace being entire 

 at its antero-lateral margins in L. nitidus and toothed in C. nitidus, but in L. edwardsi Alcock 

 we have a remarkable transitional form with the carapace toothed entirely as in Catoptrus. 

 Neither is the form of the merus of the external maxillipeds (greatly produced at antero-external 

 angle in Libystes, only slightly so or not at all in Catoptrus, according to Alcock) of importance, 



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