Crustacea Decapoda and Stomatopoda. ' 257 



The measurements are closely comparable to those of some adult females^ the 

 chief difference being that the dactylus is a little shorter in relation to the palm. De 

 Man ' records a young male specimen of this species, 65 mm. in total length, in which 

 the carpus of the second legs was g mm. in length, the palm 4^ mm. and the 

 fingers 2| mm. 



The telson tip in the Patani individuals differs conspicuously from that of 

 adults, the inner pair of subterminal spinules extending beyond the apex by more than 

 half their length. The specimens from Garia represent an intermediate stage, the 

 spinules just reaching the apex. 



Lan Chester, in his account of the Crustacea of the "Skeat Expedition," ' refers 

 to a specimen, 43 mm. in length, under the name P. carcinus var. lamarrei. This in- 

 dividual is doubtless a young P. carcinus, Milne-Edward's P. lamarrei being, as de 

 Man has shdwn,^ quite distinct from the Fabrician .species. 



Palaemon carcinus is evidently an abundant species and has a distribution extend- 

 ing from India to New Guinea and the Philippines. 



Palaemon lanchesteri, de Man. 



1901. Palaemon paucidens, I.,anchester, Proc. Zool. Soc. London, p. 568, pi. xxxiii, fig. 4 (not 

 P. paucidens, Hilgendorf, Sitz-ber. Ges. naturf. Freunde, Berlin, Jahrg. 1893, p. 155). 



1911. Palaemon [Eupalaemon) Lanchesteri, de Man {nam. nov. for P. paucidens, lyanchester 

 nee Hilgendorf), Notes Leyden Mus., XXXIII, p. 264, footnote. 



Lanchester, when describing this species, noted that notwithstanding the pre- 

 sence of ovigerous females it might eventually prove to be merely the young of 

 P. idae. In my opinion there can be no doubt that the species is valid, its nearest 

 relative being apparently P. lamarrei, Milne-Edwards. In both species the secondary 

 sexual characters seem never to be strongly developed and the second peraeopods 

 differ little, if at all, in, their proportions from those of the young. 



I have little to add tolyanchester's description. The rostrum in its length and 

 dentition agrees with his account. The posterior tooth of the dorsal series is situated 

 on the carapace, the second being as a rule immediately over the orbit ; the distance 

 between the first and second is generally not greater than that between the second 

 and third. The apex is nearly always bifid. 



The second legs are rather shorter than indicated by Manchester, those of oviger- 

 ous females reaching beyond the scales by scarcely more than the length of the chela, 

 those of males by the chela and not more than one third of the carpus (for measure- 

 ments see table on p. 258). The apex of the telson is sharply pointed, the inner pair 

 of subterminal spinules extending beyond the tip by more than half their length. 

 The eggs are large, about 1-05 mm. in length and 078 mm. in breadth. 



Sixteen large specimens and a number of young individuals were obtained by Dr. 

 Annandale at the inner end of the Tale Sap in ponds and ditches of fresh water near 

 Lampam. lyanchester records the species from Singgora, but Dr. Annandale obtained 

 no evidence that it enters the lake at that place. 



I De Man, Notes Leyden Mus., I, p. 165 (1879). 2 Manchester, Proc. Zool. Soc. London, 1901, p. 565. 



3 Pe Man, Rec. Ind. Mus., Il, p. 222, pi. xix, fig. 4 (1908). 



