336 Records of tJic Indian Museum. [Vol. XVI, 



?L?4>.?L Merg-ui Archipelago. Mas. Collr. Three (frao- 



nientar\). 

 25J_5 Diamond I., off ('. Negrais, ' Investigator.' One. 



Burma. 

 ■i«oi-2. Kaikal Maree, nr. junction S. Kemp ; Dec, iQiG. Flighty, 



of Matlah and Biddah Rs., 

 Gangetic Delta. 

 9sa9 Madah R., opposite Port Bengal Fish. Dept. (B. Seven. 



Canning, Gangetic Delta. Prashad) ; March, 



1918. 



The species is not known from an}- other locality. The 

 fragmentary specimens from the Mergui Archipelago appear to be 

 paratypes. 



Dotillopsis profuga (Nobili). 



1903. Dofilla profuga, Nobili, Boll. Miis. Torino XVHI, No. 447, p. 22. 



Upper Sadong R., Borneo. 



Genus Tympanomerus, Rathbun. 



1835, Cleistostoma, de Haan, in Siebold's Faun. Ja'-oti., Crust., p. 26. 

 1888. Dioxippe, de Man, Journ. Linn. Soc, ZooL, XXII, p. 137 {noiii. 



praeocc). 

 1897. Tympanomerus, Rathbun, Proc. Biol. Soc. Washington XI, p. 164. 

 1900. Tympanomerus, Alcock, Journ. Asiat. Soc. Bengal LXIX, p. 371. 

 1918. Tympanomerus, Tesch, Decap. Brachyur. ' Siboga' Exped. I, p. 48 



This genus shows signs of affmity with Scopimera in the form 

 of the abdomen and in the presence of accessory branchial pa.ssages 

 between the bases of the walking legs. It differs, however, from 

 both Scopimera and Dotilla and resembles Dotillopsis in the form 

 of the ultimate segments of the second maxilUped From Dotil- 

 lopsis it is readily distinguished by the absence of convolute grooves 

 on the side- walls of the carapace, by the much less strongly 

 sculptured dorsal surface and by the less broadly expanded fourth 

 segment of the male abdomen. 



Tympana, which are uniformly found in all other Scopimerinae, 

 are sometimes absent in species of this genus ; when present, they 

 are usually ill-defined and difficult to observe. 



Tesch has drawn attention to the presence of hairj^-edged 

 pouches or orifices of accessory branchial passages in species of 

 this genus. In both T. ceratophora and T. integer he found two 

 pairs, situated between the bases of the first and second and the 

 second and third walking legs. I have found these pouches in 

 T. pusillus.T- lingulatus and T. stapletoni, — in the last-named species 

 they occur between the third and fourth legs also. In five other 

 forms that I have examined the tufts of hair are absent or very 

 poorly developed and I am not satisfied that accessory branchial 

 passages exist. 



Stimpson's genus Ilyoplax, which cannot be identified with 

 certainty until the type species has been rediscovered (see p. 310), 

 is evidently related to Tympanomerus and it seems very probable 

 that the two will prove to be synonymous. Should this happen 



