aiame Uroptyclms, tail-folding, and that the accession of this fold 

 to the ordinary infolding of tlie pleon suggested the name 

 JJiptychus, double-folding. 



Gen. : Uroptychus^ Henderson. 



1880. Diptychus (pre-occj. A- Milne-Edwards, Bull Alus. Comp. 



Zool. Harvard,, vol. 8, p. 61. 

 J 888- Uroptychits, Henderson^ Challenger Anomura, Reports, 



vol. 27, p. 173. 

 1888- Diptychus, Bonnier, Bull, Sci. France-Belgique, ser- 3, vol. 



i/p- 83. 

 1892. Uroptychus, Ortmann, Zool- Jahrb., vol. 6, p. 248. 

 J 893. Uroptychits, Stehbing, History of Crustacea, p- 177. 

 1894. Diptychus, A. Milne- Edwards and Bouvier, Crust, decap- 



Hirondelle, Alonaco, fasc. 7, p. 87. 

 II 895. UroptychuSy Eaxon^ Mem. Mus. Comp. Zool, Harvard, 



vol. 18, p. lOI. 

 3899- Diptychus, A- Milne-Edwards and Bouvier, Crust, decap., 



Monaco, fasc. 13, p. 87. 

 1901. Uroptychus, Alcock, Catal. Indian Deep-Sea Crust., 



Macrura and Anoniala, p. 281. 

 The strongly developed exopod or acicle of the second antennae 

 is a characteristic feature of the sfenus. 



Uroptychus nitidus (A. Milne-Edwards). 



1JS88. Diptychus nitidus, A.Milne-Edwards, Bull- Mus. Comp. 



Zool. Harvard, vol. 8, p. 62. 

 1 888. Uroptychus nitidus, Henderson, Challenger Anomura, 



Reports, vol. 27, p. 174, pi. 21, fig. 6 . 

 1894. Uroptychus nitidus, Alcock and Anderson, Journ. Asiat. 



Soc. Bengal, vol. 63, pt. 2, p. 33 

 .1894. Diptychus nitidus, var. concolor, A. Milne-Edwards and 



Bouvier, Ann. Sci. Nat., Zool. ser. 7, vol. 16, pp. 225, 



etc., figs. 16, 21. 

 1896- Uropiychiis nitidus, var. concolor, Caullery, Campagne 



Caudan, fasc. 2, p. 393- 



1899. Diptychus nitidus, var. concolor, A. Milne-Edwards and 



Bouvier. Crust, decap. Monaco, fasc 13, p. 87, pi. i, 

 fig. 2. 



1900. Diptychus nitidus, var. concolor, A. INfilne Edwards and 



Bouvier, Crust, decap. Travailleur et Talisman, p. 360, 

 pi. 4, fig. 4, pi. 32, figs. T5-T9. 



