232 Epidemics. 



appeared south of India in the isles of the Indian Ocean 

 before 1817, but not north of the Himalayan range. 



But, in addition to fungi, is it not possible to suppose an 

 animal sarcode as perfect and yet as simple in structure as 

 the fungi (bearing in mind in all animal growth the 

 tripartite element), and capable of transportation, as a light 

 and almost impalpable dust, from person to person, as much 

 as we imagine that fungi are, as evidenced in certain skin 

 diseases which are propagated by close contact or actual 

 touch, and much easier of conveyance than the ponderous 

 acari, on the animal side, propagating their brood of ova, to be 

 kindly housed in the next neighbour's hand, who by gentle 

 contact is sufficiently felicitous to be honoured with their 

 presence ? 



Such an assumption would, in many respects, assist in 

 explaining the singular and regular successional changes 

 through which many of the zymotic diseases pass, as 

 scarlatina, variola, rubeola, and typhus, etc. And may 

 not typhus fever be counted but a mere variety of typhoid, 

 and many of the miliary and spotted fevers of old authors, 

 by accepting, in a wide and comprehensive sense, the notion 

 of an independent existence in the materia morbi of 

 infection, beyond the limit of its first and endemic origin, 

 by admitting in epidemic periods something akin to 

 the phenomena of Parthogenesis, so well established by 

 Steenstrup and Owen, etc. ; whereby it would be shown 

 that certain epidemic conditions gave to existing zooitic 

 fungi or animal fungi if the term can be allowed new and 

 independent powers of increase and extension, which, with 

 the subsidence of the epidemic, lapsed back to their former 

 endemic slums and rookeries ? Then we should get over 

 many outstanding difficulties in the way of the rise and 

 spread of infection. 



Such an assumption has often a appeared as almost an 



