44 



NILS GYLDENSTOLPE, THE SWEDISH ZOOLOGICAL EXPEDITIONS TO SIAM. 



S k u 1! 111 e a s u r e m e n t s 



Greatest length — mm. 41, o mm. 



Zygomatic width 17,0 



Width of brain caso 14,5 15,5 



Least interorbital breadth 5,7 5,6 » 



Length of nasals mesially 13,8 14,0 



Breadth of nasals anteriorly 4,0 » 3,8 



Breadth of nasals posteriorly 2,1 1,7 



Diastema 10,o 10,6 



Length of palate from henselion 17,3 19,0 



Length of foramina incisiva 7,5 7,2 » 



Length of bullae 8,1 



Maxillary toothrow C, 5 7,0 



Rattus rattus jalorensis. Bonh. 



Fasciculi Malayensis Part I. 1903 p. 28. 



ef Koon Tau, Northern Siarn, 17 /s 1914. 

 — J 1 Koon Tan % 1914. — Nose 

 $ Doi Par Sakeng, Northwestern Siarn, 19 /e 1914. 



Nose to vent = 207 mm.; tail = 225 inni.; hindfoot = 

 ef Koon Tan % 1914. - - Nose to vent =160 mm.; tail = 170 mm.; hindfoot; = 33 mm. — 



Nose to vent ==? 170 mm.; tail = 190 mm.; hindfoot = 33 mm. 



All these three specimens are similar to a specimen of Rattus rattus jalorensis Bonh. 

 from Teluk Anson in the Malay Peninsula with the exception that the tail for its whole 

 length is påle brown instead of blackish brown. The specimen obtained at Koon Tan 

 on the 17th of May 1914 has the tail påle brown with the exception of the tip which is 

 blackish brown. Apprarently a house rat and never trapped far from human habitations 



Skull measurements 



ef 



ef 



Greatest length — mm. 



Condylus to gnathion 



Basicranial length 



Zygomatic width 20,1 



Width of brain case . . • . 15,0 



Palate to henselion 19,0 » 



Breadth of palate between m l 4,0 



Diastema 10,0 



Length of foramina incisiva 6,9 



Length of nasals mesially 13,5 



Breadth of nasals anteriorly 4,9 



Breadth of nasals posteriorly 1,5 



Least interorbital breadth 5,7 



Maxillary toothrow 7,5 



38,1 mm. 





35,3 



— 



31,6 



— 



17,5 . 



18,6 



16,0 



16,2 



17,2 • 





2,9 



3,3 



9,0 





6,2 





13,2 





3,6 





1,6 



1,8 



5,4 



5,2 



6,8 



7,0 



