DIVISION I 



MYXOMYCETES, SLIME MOLDS, SLIME 

 FUNGI"-" (p. 3) 



These are the lowest organisms considered by the botanist, and 

 partake so much of the nature of both animals and plants that 

 their position has long been debated. Their affinities are with the 

 lowest living things, on the boundary between the animal and the 

 vegetable kingdom, and sometimes more attention is accorded 

 them by the zoologist than by the botanist. 



The distinctive character of this group is that the vegetative 

 condition consists either of distinct amoeboid cells or of a mass of 

 naked protoplasm, the Plasmodium, composed of numerous cell 

 units, each unwalled. The plasmodia, at the completion of the 

 free vegetative stage, produce numerous walled spores either free 

 or in sporangia of various forms. The spores upon germination 

 produce either zoospores or amoeboid bodies which multiply and 

 unite to form either new plasmodia or pseudoplasmodia. 



The slime molds consist of three orders: 



Key to Orders of Myxomycetes 



Parasitic 1. Plasmodiophorales, p. 5. 



Saprophytic 



Vegetative phase of free amoebae 2. Acrasiales 



Vegetative phase plasmodial 3. Myzogastrales, p. 9. 



The Acrasiales contain some five genera and ten species purely 

 saprophytic. 



Plasmodiophorales 



Intracellular parasites; vegetative stage plasmodial; spores 

 formed by the simultaneous breaking up of the Plasmodium into 

 an indefinite number of independent cells. 



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