v PLAGUE IN THE EAT 93 



rapidly lose its virulence, while that of the human type is 

 capable to retain it for a much longer period. 



These two types will be fully discussed presently, but 

 it is not out of place to mention here the greater danger 

 to the human species of infection with the human plague 

 type, and the much lesser danger of infection with the 

 rat plague type. 



We proceed now to consider plague in the rat — the 

 natural disease, as also the disease induced by artificial 

 means. 



Plague in Eats 1 



1. Pestis bubonica occurring naturally in rats. — I 

 have had the opportunity of examining several rats which 

 had died of true plague ; some obtained from Cardiff, 

 others from Bristol. The former had been found dead, 

 amongst many others, in and about particular docks, a 

 workman in connection with which actually contracted 

 plague (see Dr. Low's Eeport, p. 30). How the Cardiff 

 rats became smitten with the disease has not been ex- 

 plained, but the rats received from Bristol were ship rats 

 from the cargo steamer Rembrandt, coming from Smyrna 

 — a plague-infected place. 



All the above rats presented, on post - mortem 

 examination, the same appearances. The lymph glands 

 in the groin could be felt as small nodules, those of the 

 neck could be seen as dark-red spots after removal of the 

 skin. The inguinal glands were congested and showed 

 haemorrhages. Film specimens made from a particle of 

 either these or of the cervical glands showed abundance 

 of bipolar-stained oval rods corresponding in size and 



1 L.G.B. Report, 1902-1903, p. 400 and passim. 



