26 MEMOIMS OF THE QUEENSLAND MUSEUM. 



smaller and darker feet. Collett records^ an individual with intermediate colourings 

 and this variability is also borne out by Queensland Museum specimens. Hydromys 

 fulvo-venter , Jourdain, 1837 (Aim. Sci. Nat. (2), viii, p. 372), should be referred, on the 

 authority of Oldfield Thomas,^" to H. chrysogaster, and the Hydromys lutrilla " of 

 Macleay" noted by Gould in his introduction to vol. i of the " Mammals of Australia" 

 should probably be included in the same synonymy. 



Hydromys fuliginosus, Gould. 



1863. — Hydromys fuliginosus, Gould, Mamm. Austr., iii, -p\. xxvii. 



1906. — Hydromys fuliginosus, Thomas, P.Z.S., p. 765. 



Type locahty : Perth. 



This West AustraUan form should be regarded as a distinct species. 



^Hydromys beccarii, Peters. 



1874. — Hydromys beccarii, Peters, Mus. Civ., \'i, p. 303. 



1881. — Hydromys beccarii, Peters & Doria, Mus. Civ., xvi, p. 706, jjl. xviii. 



1897. — Hydromys beccarii, Thomas, Mus. Civ., xviii, j). 609. 



Type locahty : Key Island. 



^Hydromys esox, Thomas. 



1906. — Hydromys esox, Thomas, Ann. Mag. Nat. His., xvii, p. 324. 



T3rpe locality : Port Moresby, Papua. 



Genus XEROMYS, Thomas, 1889. 



Terrestrial, but dentition as in Hydromys. " External form murine. Tip of 

 muzzle as in Mus, not as in Hydromys. Toes unwebbed. Tail scaly, very finely haired. 

 Skull as in llus, except that the supraorbital edges are rounded." 



Xeromys myoides, Thomas. 



1889. — Xeromys myoides, Thomas, P.Z.S., p. 248. 

 1892. — Xeromys myoides, Ogilby, Cat. Austr. Mamm., p. 102. 

 Type locahty : Port Mackay, Queensland. ^^1^ 



Of this remarkable rodent Oldfield Thomas says (loc. cit.) : " That Xeromys 

 is the almost unmochfied descendant of one of the more recent ancestors of Hydromys 

 is almost unquestionable, as it does not possess a single pecuhar characteristic of its 

 owai, every one of its points being present either in its relatives the true Rats and Mice, 

 or in what we may fairly call its offspring, Hydromys." 



The Phihppine rat, Xeromys {?) silaceus, Thomas (Ann. Mag. Nat. His., vi, 16, 

 1895, p. 161), has since been placed in the genus Celcenomys, Thomas. 



*Genus PARAHYDROMYS, Poche, 1906. 

 Less speciahsed for aquatic hfe than Hydromys. 

 *Parahydromys asper, Thomas. 



1906. — Limnomys asper, Thomas, Ann. Mag. Nat. His., xvii, p. 325. 

 1906. — Parahydromys asper, Poche, Zool. Anz., Leipzig, 30, p. 326. 



9 Collett, Zool. Jahr., 1887, p. 841. 

 1° Thomas, P.Z.S., 1908, p. 790. 

 Note. — Species not Australian or Tasmanian are denoted by an asterisk. 



