76 FROM AN EASY CHAIR 



there is a third kind, which is the commonest of the 

 three in Calcutta, and is probably the one most con- 

 cerned in the dissemination of plague. It differs in 

 some definite features from both the Black rat and 

 the Grey rat, although it is very much like the latter 

 in general appearance. It is called Nesokia Bengalensis, 

 or Mole-rat. It is a big rat its tail is only 70 per 

 cent, the length of its body; the pads on the soles 

 of its feet differ from those of the two other rats; 

 its fur is thin and bristly, and when it is put into a 

 cage it erects its bristles and spits ! It is, like the 

 Black rat, a stable and granary rat, and makes burrows 

 in which it stores grain. 



The rats of Calcutta have been carefully studied 

 lately by Dr. Hossack, in consequence of their con- 

 nection with the bubonic plague. In the older native 

 parts of Calcutta, the Mole rat is twice as common 

 as the Norwegian Grey rat, and the Black rat not so 

 abundant as the latter. In the central European 

 part of the town the Grey rat is commoner than the 

 Mole rat because, apparently, the better-built houses 

 do not afford such facilities for burrowing. The Black 

 rat is here also by a good deal the most uncommon of the 

 three. All these rats suffer from the plague, die from 

 it, and the fleas which lived in their fur leave them 

 as they get cold, and make their way on to human 

 beings, whom they consequently infect with the plague 

 bacillus. This has now been quite conclusively proved 

 by the Indian doctors charged by Government with the 

 study of the causes of the plague. The plague bacillus 

 a minute, rod-like organism, which grows in the 

 blood and lymph, once it has effected a lodgment, 

 and there produces deadly poison was discovered some 

 fourteen years ago, but it is only recently that the 

 plague bacillus has been shown to live in the intestine 

 of the flea, which sucks it up with the blood or other 

 fluids of the rat on which it lives. The flea, which 



