RATTUS BLYTHI. ' 67 



All these rats are medium -sized animals with tawny to elay- 

 coloured upperparts thickly sown with flattened spines having 

 pale horny green bases, strongly margined whitish or creamy 

 underparts and bicoloured tails (except cremoriventer), while the 

 bullae are small and flattened. 



Others of the same group, not referred to above, are : — 

 R. pan, 6 like bukit ; but the white of the underparts not extending 

 to the hind feet, interpterygoid space more abruptly truncate 

 anteriorly, rostrum rather heavier and nasals longer. Rattus pan and 

 marinus are undoubtedly local forms of R. bukit, whereas 

 gracilis and orbus probably represent jB. rapit Bonhote (t. c, p. 123) 

 from Kina Balu, North Borneo. 



A rat not known to me by topotypical examples is R. lepidus. 7 

 A single specimen from North Siam referred to it 8 -except for 

 decrease in the number and size of spines - seems not to differ 

 materially from R. bukit. 



I have seen no specimens of R. gracilis 9 which Mr. Thomas 

 stated (1. c.) to be closely allied to R. bukit, but later (in litt.) 

 concludes is the same as R. orbus : if so it is quite different from 

 blythi and from bukit; and it must be admitted that while orbtts 

 was being described gracilis was entirely over-looked. 



Rattus sakeratensis 10 I am quite unable to place for the 

 present ; it was founded on a single specimen which I have not 

 seen. 11 



The following are the description and measurements of Mr. 

 Gairdner's series of Rattus blythi : — 



Upper pelage thickly set with broad spines with greenish 

 bases and grey tips : rump sown with long black-tipped piles. Tail 

 dark above and whitish below. Colour above cinnamomeus, inter- 

 mediate between ochraceous-tawny and the same tinged with amber- 

 brown ; the back streaked by the blackish tips of the spines : base of 

 fur grey. Head, sides and limbs more ochraCeous-buffy. 



6, 7, 8, 9, 10, 11. Vide Notes on page 68 postea. 

 VOL. IV. NO. 2, 1920. 



