91 6 



THE ANIMAL CARRIERS OF DISEASES 



The tail, which is 25 per cent, longer than the length of the head and body 

 together, is brown and regularly annulated. Feet medium-sized, but compara- 

 tively long and slender. 



Body variable, 14 to 19 centimetres in length. Colour variable: light 

 rufescent, brown on the dorsum, white or grey on the venter, but may be 



darker or lighter. Mammae two to 

 three. 



There are two varieties of this 

 rat: alexandrinus, which is larger 

 and heavier; and rufescens, which 

 is smaller and redder; but there 

 are any number of intermediate 

 species. It breeds frequently 

 throughout the year. 



It is essentially a house rat, 

 living in the tiles or thatch of the 

 roof, or in holes and recesses in 

 the floor, but it will live in the 

 crowns of cocoanut trees. 



Its pathogenicity is important, 

 for it is the plague rat of Upper 

 India. It is supposed to have 

 entered Europe with the Asiatic 

 invasion. 



Eplmys norvegicus Erxleben. 1777. 



Synonym.— Mus decumanus 

 Pallas, 1778. 



Large, heavy rats, with heavy, 

 uniformly tapering tails; dark 

 coloured dorsally, lighter coloured 

 ventrally; only 89 per cent, of the 

 length of the head and body. 

 Heavy, flesh-coloured feet, short 

 round ears, and broad heavy 

 snout. 



Colour brown on the dorsum and 

 dirty white on the venter. Foot- 

 pads large; heart-shaped mammae 

 Reservoir. ten to twelve in number. 



Fig. 474. — Rat: Plague 



