94 Records of the Indian Museum. [Vol. Ill, 



of Mils vicerex, because they resemble in their peculiarities certain 

 rats which were caught in Simla in 1896. The common rats of 

 Simla are to-day different from the common rats of Kashmir, which 

 form a distinct race. 



Race 2 {Mus nitidus ?). — Rats caught this year in six differ- 

 ent parts of the Darjiling district all agree in possessing relatively 

 short tails, thick, soft, greyish fur, dark under parts and feet pure 

 white above with black soles. They are of course variable like 

 all other rats, but their variability is about a mean other than that 

 of the common rats of the plains. Hossack, who caught two of 

 these rats, regarded them as Mus nitidus. 



Race 3 {Mus hlanfordi). — In 1881 a peculiar rat was found at 

 Kadapa in the Nilgiri Hills of Madras, and a little later another 

 resembling it was found at the same place ; both of these rats were 

 distinguishable from the common type by the following features. 

 The fur was thick and soft, greyish fawn above, white below,, the 

 ears were large ; their tails were most peculiar, the}' were relatively 

 long, and pure white in the distal half, the hair on the tail was un- 

 usually long and formed a terminal tuft. There are in the Indian 

 ^luseum four other precisel}^ similar specimens from the Shevaroy 

 Hills which are nearly 200 miles from Kadapa, to the east of the 

 Nilgiris. The peculiarities which were originall}- described in the 

 skull of the ' ' type ' ' specimen are not constantly found among 

 the four from the Shevaroy s, which do not seem to differ in this 

 respect from many of the common rattus type. There can, however, 

 be no doubt that M. hlanfordi is an established race ni the Nilgiris. 



Race 4 {Mus jerdoni). — Rats have been frequently obtained from 

 the Himala^^as of Sikhim and Assam which are peculiar in being 

 bright rufous above, white below, and in possessing remarkably 

 long bicoloured tails. In 1881 a close observer noticed that of live 

 of these rats, all possessed a minute accessor}' palatal ridge between 

 the two posterior ridges (.4th and 5th) [2]. There are in the Indian 

 Museum several similar rats ; among them are three litters of 3^oung 

 ones, two from Darjiling of two each, and one of three from Cherra- 

 punji (Assam). Every member of each litter shows some irregu- 

 larity of the posterior palatal ridges tending towards the inter- 

 polation of an extra one. 



The number and form of the palatal ridges is most constant 

 among rats. Besides the cases just referred to, the writer has onl}' 

 once found an abnormality in these structures although he has 

 examined large numbers of them both in Gunomys and Mus. 



The skulls of the Mus jerdoni in the Indian Museum could be 

 distinguished from hundreds of the common rattus type owing to 

 their remarkably small auditory bullae. This point was discovered 

 in other specimens in 1881. Mus jerdoni is therefore a distinct 

 race in the Eastern Himalayas. It is said to occur in Java. 



These are the only four special races of the Mus rattus type 

 in the Peninsula of India of which we have sure evidence, although 

 there must be many others. Local races showing albiventralism 

 seem to be established in several places. One cannot assign a local 



