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The animal is of a reddish-yellow colour, with irregular, large, reddish blotches on the 

 anterior half of die carapace. 



Dana records the species from New South Wales or New Zealand, the exact locality 

 beino- apparently unknown. Ortmann mentions two specimens from Tahiti, but unfortunately 

 he gives no description. If my determination be right, the species also occurs at Lombok. From 

 //. latreilli it is certainly distinct, though it is closely related to that species. 



Dimensions in mm. : 



Distance between external orbital angles 12. — 



.Maximum breadth of carapace 13.5 



Length of carapace JO-75 N 



Posterior margin of carapace 7-5 



Length of cheliped 21. — 



Horizontal length of chela 9.5 



Height of palm 6. — 



Length of movable ringer 5-5 



Breadth of 3 d segment of abdomen 6.7 ') 



Length ) \ 2.2 'j 



_ , , , f of 6 tn segment of abdomen . .. 



Breadth at base \ (3-3 ) 



Length ) \ 1.65 ') 



} of terminal sesrment of abdomen { . ., 



Breadth at base \ ö ( 1.8 ') 



Chasmagnathus de Haan. 



1835. Chasmagnathus de Haan. Faun. Japon., Crust., p. 27. 



This genus is distinct from FIclicc by the postero-lateral margins of the carapace being 

 convergent and the antero-lateral margins divergent backvvard, by a generally broader shape 

 of the abdomen of the cT, by the palm of the chelae being longer than high, and by the 

 merus of the external maxillipeds being nearly half as broad anteriorly as long and much 

 more elongate than in Helice. 



Thus restricted the genus includes only the well-known Japanese species Ch. convexus 

 de Haan -). Now Herklots in his Symbolae carcinologicae 3 ), that deal with the collection ot 

 Crustacea in the Leiden Museum, mentions two new species: Ch. gibbosus de Haan M.S. 

 from Java, and one, unnamed, from Abessynia. The latter species I have not found back; 

 Ch. gibbosus is represented by three specimens (all Q, dried), one of which is a new species 

 of Sarmdtium {fryatti), already described in my paper on Sesarma etc. 4 ) and the remaining 

 specimens undoubtedly belong to Ch. convexus. The locality (Java, Kuhl et van Hasselt coll.) 

 seems to me to be probably erroneous, and perhaps the two specimens of CJiasmagnathus 

 have been mislaid. 



1) Measured under microscope. 



2) Ocypode (Cliasmagnathns) convexus de Haan, Faun. Japon., Crust., 1835, p. 56, pi. 7, f. 5: ADAMS et White, Zool. Voy. 

 "Samarang" 1850, p. 52; Chasmagnathus convexus H. Milne-Edwards, Ann. Sc. Nat. (3) t. 20, 1853, p. 200; Ortmann, Zool. Jahrb., 



.. 1! 7, 1894, p. 727; Stimpson, Smithson. Inst., Miscell. Coll., v. 49, 1907, p. 133. Hab. Japan and Loo-Choo Islands. The specie- 

 ribed 1 >y Haswell under this name (Cat. Austral. Crust., 18S2, p. 106) is, as Oktmann rightlv remarks, certainly different from that 

 Haan, and it cannot even be traced to which genus it should belong. 



3) Tijdschr. Entomol., t. 4, 1861, p. 128. 



4) Zool. Mcd. Mus. Leiden, v. 3, igi 7, p. 216, textfig. 6. 



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