728 OLDFIELD THOMAS. 



17. y Rat 'tus bandiculus, Thos. 



f 25. Pionier-bivak, Mamberamo River. W. C van Heurn, 18 Dec. 1920. B. M. N°. 22.2.2.22. Type. 



A still larger and heavier form of the same group as the preceding. 



External characters as in coenorum, the colour of the single old spécimen being as in 

 old examples of that animal. Feet thick and clumsy. 



Skull conspicuously larger in ail dimensions than that of coenorum. Nasals long, broad 

 in front, narrovved in their posterior two-thirds. Cranial ridges strong. Palatal foramina large 

 and open, reaching back to the level of the front of m 1 . 



Dimensions of the type, measured in flesh : 



Head and body 252 mm.; tail 220 ; hindfoot 49 mm. 



Skull, greatest length 54; condylo-incisive length 52.6; zygomatic breadth 27.5; nasals 

 20; interorbital breadth 7; breadth across ridges on braincase 16.2; zygomatic plate 6.3; 

 palatilar length 27.6; palatal foramina 10.6X4.8; upper molar séries 9.1. 



Hab. and type as above. 



This large rat, of \vhich unfortunately only one spécimen was obtained, seems, unless 

 it proves to hâve a différent mammary formula, to be only distinguishable from the last by 

 its much greater size, especially by its very large skull, which Mr. VAN HEURN thought to 

 be that of a Bandicoot. Comparison between its cranial dimensions, and those of the second 

 spécimen of coenorum, equally aged, measured above, vvill show hovv great is the différence 

 between the two, so that it is impossible to consider them to belong to the same species. 



[Rattus rïngens, Pet. 



9 in al. Kloof-bivak, Lorentz River. Dr. Versteeg.] 



18. f Stenomys arrogans, Thos. 



rf. 189. Ç> 1S4, 185, 194, 196. Doormanpad-bivak, 2400 m. W. C. van Heurn. 



A médium sized species with a much swollen braincase. 



Size less than in verecundus, slightly greater than in klossi. Fur long, soft, hairs of 

 back about 12 mm. in length. General colour as usual very dark — dark bistre brown faintly 

 ticked with bufiy, about as in S. klossi and nïobe; the under surface also brown. Fingers 

 lighter brown : metacarpals, whole of hind foot and tail dark brown. Mammae 1 — 2 = 6. 



Skull with normal narrow muzzle but much broadened and peculiarly swollen brain- 

 case, the swelling commencing in the interorbital région and increasing in the much inflated 

 cranial portion. Palatal foramina narrow, fairly long, ending in front of m 1 . Bullae about as 

 in 5. klossi. 



Dimensions of the type, measured in flesh: 



Head and body 120 mm.; tail 125; hindfoot 25.5. 



Skull, greatest length 34; condylo-incisive length 30.6; zygomatic breadth 17; nasals 

 12.5; interorbital breath 6.6; breadth of braincase 15.5; palatilar length 14.4; palatal fora- 

 mina 5; post-foraminal palate 7.3; upper molar séries 6. 



Hab. as above. 



Type. Adult female. B. M. N°. 22. 2. 2. 24. Original number 196. Collected 3 1 Oct. 1920. 



