70 JOURNAL, BOMBAY NATURAL HIST. SOCIETY, Vol. XXVI. 



The skull is small (average condylo-basal length between 37'7 

 and 38-4 mm., i.e., about 2 mm, less than in European races of 

 R. rattus or in R. r. sikkimensis), and therefore the cranial width 

 appears relatively great, showing an increase equal to from 1 

 to 1*7 per cent, of the condylo-basal length (see Table 11). 

 Judging from dimensions 6 and 7, as well as from the relation of 

 the latter to the cranial width, (dimension 3), the temporal muscles 

 are no weaker than in R. r. aUxandrinus. Posteriorly, ep^en in old 

 skulls, the temporal lines are at a level considerably below the ends 

 of the iiiterparietal ; and thus the upper surface of each parietal 

 articulates with the supraoccipital by a conspicuous tongue. The 

 temporal wing of each parietal is small, its length being equal to 

 less than half the distance between the lambdoidal crest and 

 the antero-superior extremity of the squamosal. 



In relation to the condylo-basal length, the palatal length, mas- 

 seteric plate and tooth-rows are distinctly longer, although the 

 nasals, diastema and palatal foramina are about as in European 

 rattas. The pterygoid region is short, for while the distance con- 

 dyle to bulla is about as in R. r. frvgivorus, condyle to m. 3, in 

 relation to the oondylo-basal length, is about 3 y shorter. The 

 cheek-teeth are as in European ratlus. 



Local variation : — 



Narbong (2,000'). 



14 (7 c? , 7 2 ) collected by Mr. Crump; of these 2 are in the 

 British Museum (Nos. 15, 9, 1, 152-153). The dimensions of the 

 more important are : — 



6439 c? , 10 March 1915, 176—206—35—23, Weight 6 czs 

 •152 6473c?, 14 „ „ l(jl_195— 34— 23 



6474 J, „ „ „ 165—180—32—22 



6479$, 15 „ ,. 154— 176— 33— 21, Weight 4 czs 



•153 6480$, „ ,, „ 156—179—31—24 „ 4 ,. 



6487$, „ „ „ 144—171—31—20 „ 3 „ 



Average of 14:— 156— 182— 32-2-21-7 



Do. per cent.of H&B:— 100— 117— 20-7-13-9 

 10 mammae are apparent in each of 4 of the female skins. 

 These rats have rather bright backs and are much like those 

 from Rongli noticed below. In 5 (3 c? , 2 $ } the bellies are pure 

 white, although in 4 of these some of the hairs on the chest have 

 slaty bases. In the remainder the majority of the ventral hairs have 

 slaty bases and in some a median stripe of buff* is developed on the 

 thorax. The whole series is, however, very uniform really, for 

 even the bellies, despife the differences just noted, appear remark- 

 ably similar when viewed from a little distance. Skull as in 

 typical series. 



