270 On a new Btnturong from Siam. 



XXVII. — A new Bint urong from Siam. 

 By Oldfield Thomas. 



(Published by permission of the Trustees of the British Museum.) 



Amonq a collection of mammals from Soutli-westevn Siam 

 presented last year to the National Museum by Mr. K. Gt. 

 Gaiidner there occurs a fine binturong's skull, so conspicu- 

 ously larger than any other known that it evidently represents 

 a distinct species. I liave, however, not been able to describe 

 it before, owing to a doubt as to what sexual variation tliere 

 might be in the genus and the fact that all our adult skulls 

 appeared to be those of females. Now, however, thanks to 

 the kindness of Mr. H. C. Robinson, I have before rae a fine 

 male skull from Bukit Gautang, Perak, and am thus able to 

 make a proper comparison with the Siamese animal. This 

 latter may be called 



Arctictis gairdneri^ sp. n. 



Size conspicuously greater than in the other species. 

 Skull broader, more vaulted. Nasals very broad, parallel- 

 sided to the point where they join the frontals laterally, 

 instead of evenly narrowing from front to back. Frontal 

 region broad, much swollen upwards and laterally, then 

 abruptly narrowed at the fronto-parietal suture. Sagittal 

 and lambdoid crests greatly developed. Posterior palate 

 broad, much produced backwards. Bullae narrow, far over- 

 lapped by the heavy paroccipital processes. Teeth much 

 worn down in the type, their proportions apparently about as 

 in the Perak skull. 



Dimensions of the type (those of the Perak male in 

 brackets) : — 



Greatest length 153 mm. (136) ; condylo-basal length 

 152 (136) ; zygomatic breadth 98 (84'5) ; nasals, mesial 

 length 28 (21), breadth at middle 19 (12) ; interorbital 

 breadth 41 (33) ; tip to tip of postorbital processes 59 (47-5) ; 

 breadth immediately behind the latter 51*5 (40) ; breadth at 

 fronto-parietal suture 41 (39) ; greatest posterior breadth on 

 ridges 73'5 (59) ; height of crown from posterior palate 

 54-5 (47) ; palatal length 84*5 (73) ; breadth of posterior 

 palate 24-5 (19'7). 



Hah. Sai Yoke, S.W. Siam, near Tenasserim boundary. 



