South African Crustacea. 73 



GEN. PALAEMON, Fabricius, s.s. 



1798. Palacmon (part), Fabricius, Suppl. Ent. Syst., pp. 378, 402. 



1891. Eupalaemon (subgenus), Ortmann, Zool. Jahrb., vol. 5, 



pp. 696, 697. 



1892. de Man, in Max. Weber's Zool. 



Ergeb. Niederl. Ost.-Indien, 

 vol. 2, p. 410. 



1902. ,, ,, de Man, Abbandl. Senck. Nat. 



Gesellsch., vol. 25, pt. 3, p. 763. 



1904. ,, ,, de Man, Trans. Linn. Soc. London, 



vol. 9, pt. 8, p. 291. 



1905. Coutiere, Ann. Sci. Nat., Ser. 8, 



vol. 12, pp. 263, 273. 



1911. ,, ,, de Man, Notes from Leyden Mus., 



vol. 33, p. 281. 



1912. ,, ,, de Man, Eev. Zool. Africaine, 



vol. 1, pt. 3, p. 413. 



1912. ,, ,, de Man, Ann. Soc. Zool. Belgique, 



vol. 46 (1911), p. 197. 



PALAEMON SUNDAICUS, Heller. 

 (See these Annals, vol. 6, pt. 4, p. 384, 1910.) 



The distinction of species in this family has been made largely 

 to depend on the size, shape, and denticulation of the rostrum, the 

 roughness or smoothness of the carapace and limbs, the relative 

 proportions of various joints, details in the shape and armature of 

 the chelae, and even on the position of small spines pertaining to the 

 telson. Unfortunately for the systematist several of these characters 

 are found to vary with the age or sex of individuals, and in some of 

 these they may be obscured by wear and tear or by natural abnor- 

 mality. While, therefore, it may be easy to say that such and 

 such a species has been found in this or that locality, it may be a 

 tedious business to confirm the statement. 



The specimen here assigned to Heller's species is 100 mm. long, 

 the carapace with the rostrum measuring 45 mm., and the telson 

 13 mm., equalling the length of the fifth and sixth pleon segments 

 combined. The slightly imperfect rostral carina carries 10 or 11 

 dorsal teeth, much the longest interval being between the foremost 

 2 or 3 teeth and that next behind them ; two of the teeth are behind 

 the orbits ; among the setules of the ventral margin 3 small teeth 



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