38 



Memoirs of the Indian Museum. 



[Vol. I, 



in immature rats. The normal proportion is I7"4 per cent, with extreme variations 

 of 15 to 21 according to the age, though in Nesokia scullyi it is said to be 26 even 

 in the adult. The ear, too, is like the foot, abnormally large, 2 cm. over the maximum 

 which is found only in very large specimens about 20 cm. long ; it is I3"2 per cent- 

 of the body-length against an average of 107. The idea suggested by the external pro- 

 portions that the rat was immature, was fully confirmed by an examination of the teeth, 

 as they are quite unworn and show very clearly the rudimentary extra laminae in the 

 second and third upper molar. The upper molar series, moreover, is much too large 

 to be that of Nesokia bengalensis, being 10 x 3 mm. against an average of 7 x 2'6, with 

 a maximum of 8x3. The characters of the skin are quite unlike those of Nesokia 

 hengalensis ; the general colour is lustrous steely grey with deep brown along the 

 back. The under surf ace is dark grey, with only a trace of white- tipped hairs ; long 

 piles are present, but closer set and finer than in Nesokia hengalensis , and rich brown 

 rather than black in colour. There is thick grey underfur. Altogether it is rather a 

 handsome rat, very different from the rusty, coarse-coated rat with which it has been 

 confused. The tail also is too finely and regularly annulated ; the feet are covered with 

 fine brown hair. The skull is larger than that of Nesokia hengalensis , 43 x 28 mm. 

 against an average of 40 x 23 '8 in my series ; in the Indian Museum it is true there 

 are skulls of this size, but these are very old skulls as shown by the worn down teeth and 

 the greatly developed muscular ridges. The skull in dispute shows much larger teeth, 

 and all the characters of an immature skull. If, on the other hand, we compare it 

 with the skull of the immature N. handicota whose body dimensions have already 

 been given, — No. 222 of my series, — it will be found that the dimensions are almost 

 similar. Altogether I can only come to the conclusion that instead of being an adult 

 N . hengalensis it is an immature specimen of Nesokia handicota, though to which 

 variety it belongs I am not in a position to say. There is the possibility that it may be 

 a new species characterized by the same exceptional breadth of the cranium and size of 

 the foot as is shown by the recorded measurements of Nesokia scullyi, but the material 

 so far collected as to the measurement of the different members of this genus is so 

 scanty that much will have to be done before the identity of this and the J agdispur 

 specimens can be definitely settled. A note on the J agdispur rats will be found later on. 



Comparison of skull measurements of Kilakarai skull with that of immature 



N. handicota. No. 222. 





G.,L. 



Basal 



L. 



G.B. 



24 

 55-2 



N.L. 



lo. B. 



C.B. 



Zg- 

 PI. 



625 

 14-2 



5 

 11-4 



Pal. 

 L. 



25 



66-8 



24 

 55- 1 



Diast. 



13 

 29-5 



Ï3 



29-8 



Pal. 

 For. 



8 

 181 



8-5 

 19-5 



Pal. 

 F.B. 



3-5 

 7-9 



3 



6-8 



Up. 

 M.L. 



Up. 

 M.B. 



Lower 

 C. to I. 



Jaw 



C. to 



A. 



Immature A'^. 

 handicota. 



Ki 1 a k a r a i 

 skull. 



44 

 100 



435 

 100 



40 

 91-9 



1475 

 33-5 



16 

 36-7 



7 

 15-9 



8 

 18-3 



17-5 

 39-7 



18 

 41-3 



10-5 



23-8 



10-25 

 23-5 



35 

 7-9 



3-5 



8-0 



31 



70-4 



15 

 34 



