186 MICHOBES, FERMENTS, AND MOULDS. 



they appear in increasing numbers, and their maximum 

 corresponds with the beginning of the rise in tempera- 

 ture; from that moment they begin to perish, since 

 the heat of fever is fatal to them, and completely 

 checks their development. This explains the inter- 

 mittent character of the disease. They produce fever, 

 the fever kills them and then subsides ; when apyrexia 

 occurs they multiply again, excite fever, and so on." 

 Thus tl.ere is a successive series of auto-infection by 

 the parasite itself, unless its development is arrested 

 by sulphate of quinine. "The parasites of typhus 

 and typhoid fever are not affected by a temperature 

 of 40, and even of 42, and hence the continuous 

 character of these fevers." 



Cornil has, with some justice, criticized Laveran's 

 description and illustrations of the parasite of marsh 

 fever. It is difficult to recognize in it an organism 

 really belonging to the animal or vegetable kingdom. 

 The form of the filaments which, as he asserts, issue 

 from the so-called encysted bodies, resemble those 

 which Hoffmann has seen and drawn in blood in its 

 normal state, and also in various diseases, and are 

 probably only expansions of extravasated protoplasm 

 in the red corpuscles at a temperature of 40. The 

 encysted bodies are also, according to all appearance, 

 only blood-corpuscles, more or less affected by disease. 



There only remain the pigmented, encysted granules 

 in the red and colourless corpuscles, granules which 

 have been observed by others, and especially by 



