KUNGL. SV. VET. AKADEMIENS HANDLINGAR BAND 60. NIO 6. 



43 



w. whitéheadi are buffy ochraceous, while these same parts are »lavender grey» in R. 

 w. perlutus. This latter form is also stated to have a larger skull. 



The two specimens in the present collection have the upper surface of the 

 body hazel, though the blackish tips to the spines are showing through especially 

 along the central dorsal region. The sides of the body and whole underparts buffy 

 ochraceous. Tail blackish brown above, slightly paler below. Hands and feet white. 

 Whiskers and eye-bristles black. Fur very spiny. 



R. w. whitéheadi \R. w. perlutus 



Skull measurements : 



9 

 No. 131 



ef 1 

 No. 37. 



(Type) 



Greatest length of skull 



Length from condylus to gnathion 



Basicranial length of skull 



Zygomatic width 



Greatest width of braincase 



Least interorbital width 



Length of nasals mesially 



Breadth of combined nasals anteriorly .... 

 Breadth of combined nasals posteriorly .... 



Diastema 



Length of foramina incisiva 



Greatest breadth of combined foramina incisiva 



Length of upper toothrow (alveoli) 



Lengtli of lower toothrow (alveoli) 



33,6 



29,8 



27 2 



14,6 



13,2 



5,2 



12,3 



2,9 



l, 3 



8,4 

 4,3 

 2,1 

 5,3 

 4,5 



32,3 

 29,6 

 26,9 

 15,1 

 13,3 



5,2 

 12,2 



3,1 



1,4 

 7,7 

 5,2 

 2,5 

 5,3 



35,5 



15,5 



5,7 

 U,7 



9,0 



4,5 

 2,4 

 5.S 



40. Rattus muelleri Jentink. 



Notes Leyden Mus., 1879, p. 16. 



No. 8. (£ Kaboerau, Eastern Borneo 11 /i 1914. Head and body: 206 mm. Tail: 252 mm. Hindfoot: 

 42 inm. Ear: 23 mm. — No. 7. $ Kaboerau, Eastern Borneo n /i 1914. Head and body: 224 mm. Tail: 

 245 mm. Hindfoot: 42 mm. Ear: 21 mm. — No. 116. $ Long Palabar, Boelongean, Eastern Borneo b jb 

 1914. Head and body: 203 mm. Tail: 261 mm. Hindfoot: 43 mm. Ear: 21 mm. — No. 115. <g Long 

 Palabar, Boelongean, Eastern Borneo B /ä 1914. Head and body: 214 mm. Tail: 265 mm. Hindfoot: 41 mm. 

 Ear: 20 mm. 



These four large Råts must certainly be referred to the species described by 

 Jentink (tom. cit.) under the name of Mus muelleri. The type was obtained on 

 Sumatra, but it has also been recorded several times from Borneo. 



They are large Råts almost of the same size as R. infraluteus Thos., from which 

 they may be separated by the different colour of the underparts of the body. The 

 fur is coarse, rather soft and without spines or longer bristles. In colour they are 

 coarsely lined black and yellowish buff. The underparts of the body are whitish 

 buff , the bases of the hairs being almost \* hitish. The colouration of the underparts 

 is not sharply defined from that of the sides of the body. 



