568 



HUTCHINSON'S POPULAR BOTANY 



which develop into filaments again by cell-division. The hardiness of 

 most species is astonishing : they stand extremes of heat and cold, may 

 be desiccated and remain alive for years, and some even retain their vitality 

 in alcohol. Like the Fungi, they include both saprophytes and parasites. 

 The saprophytes work chiefly by causing decomposition and fermentation ;' 

 the parasites affect living animals, rarely living plants. As they are at 

 least the accompaniment of many diseases in the human body, attempts 

 have been made in some quarters to regard them as the specific cause 

 of most diseases. Whilst there is no doubt that their malignant agency 

 has been established in some of these (e.g. Bacillus anthracis in splenic 

 fever, and the Comma Bacillus in Asiatic cholera), it must not be supposed 

 that all Bacteria are to be looked upon with dread as human enemies. 

 Many of them are known to be beneficent towards humanity, and others 

 science has learned to educate, as it were, to service in the arts and 

 manufactures. 



Respecting the MYXOMYCETES, or MYCETOZOA as they are variously called, 

 there is still an amount of disputation as to their true position. By some 



they are re- 

 garded as a 

 group of 

 fungi, and 

 known as 

 Slime 

 Fungi, 

 the ref or e 

 proper to be 

 included in 

 a work on 

 Botany ; but 

 others con- 

 ten d for 

 their animal 

 nature. Pro- 

 duced from 

 microscopic 

 spores, they 

 emerge as a 

 kind of Am- 

 oaba (swarm- 

 cells) that 

 glide with a, 

 streamin g 

 movement r 

 t h rusting 



FIG. 717. Mucilago spongiosa. 



[E. Step. 



One of the Myxomycetes that may be found in pastures climbing up the stems of grasses 

 and weeds to form its sethalia. 



