South African Crustacea. 7 



fall short of it." He divides it into three sub-families Xanthinae, 

 Actaeinae, and Chlorodinae which I prefer to treat as families, 

 accepting for the first the name Xanthidae in a restricted sense. 

 For this Alcock's definition is : " Carapace usually much broader 

 than long, usually transversely oval, sometimes transversely hexa- 

 gonal. The front is contained from 3i to 5| times in the greatest 

 breadth of the carapace." 



It is subdivided into six so-called alliances, the fourth of which, 

 called Xanthoida, contains among others the typical genus Xantho, 

 Leach, followed by Leptodius, which is presently reduced to a 

 sub-genus of Xantho. 



The remarks made by Miers in his Alert and Challenger 

 reports on the species which have been referred to Leptodius, A. 

 Milne-Edwards, 1863, will incline many to agree with Dr. Ortmann, 

 when he says (Zool. Jahrb., vol. vii., p. 443, 1893) : " I am unable 

 sharply to distinguish the three genera Xantho, Xanthodes, and 

 Leptodius." The last is chiefly distinguished by the spoon-shaped 

 tips to the chelipeds. But Ortmann observes that a typical Xantho 

 (rivulosus) has them, and Alcock remarks that in Leptodius crassi- 

 manus the spooning of the figures is indistinct. The latter species 

 is, perhaps for that reason, referred to Xantlio by Miss Rathbun 

 in 1906. 



GEN. XANTHO, Leach. 



1814. Xantho, Leach, Edinburgh Encycl., vol. vii., p. 430. 

 1898. Xantho, Alcock, Journ. Asiat. Soc. Bengal, vol. Ixvii., pt. 2, 

 p. 112 (including Leptodius). 



XANTHO HYDROPHILUS (Herbst). 



1790. Cancer hydrophilus, Herbst, Naturg. Krabben u. Krebse, 



vol. i., pt. 8, p. 266, pi. 21, fig. 124. 

 1801. Cancer Eudora, Herbst, Naturg. Krabben u. Krebse, vol. iii., 



pt. 2, p. 10, pi. 51, fig. 1. 

 1826? Cancer incequalis, Audouin, Savigny's Crust. Egypte, pi. 5, 



fig. 7. 

 1834. Chlorodius exaratus, Milne-Edwards, Hist. Nat. Crust., vol. i., 



p. 402. 



1834. [?] Chlorodius eudorus, Milne-Edwards, loc. cit., p. 402. 



1835. Cancer (Xantho) affinis, de Haan, Crust. Japon., decas secunda, 



p. 48, pi. 13, fig. 8 (f. 6 in text). 

 1843. Xantho affinis, Krauss, Siidafrik. Crust., p. 30. 



