162 



MANUAL OF POISONOUS PLANTS 



{plication, as before stated, is by simple fission or cell division. Growth takes 

 ^lace very rapidly in many forms, some being capable of growing to their full 

 size and dividing to form two individuals in twenty minutes to half an hour. 

 Under favorable conditions, this rapidity of multiplication explains the import- 

 ance of the results obtained, and the products formed from such small plants. 

 Some forms are capable of moving or swimming about by means of whips or 

 flagella placed on all sides or simply at the ends. Other forms move by a 

 sinuous or snake-like bending of the body. Many forms are incapable of motion. 

 Spores are formed by many species; they are called endospores when formed 

 singly within the bacterial cell, and arthrospores when formed by increase in 

 size of the cells of the filament or part of a filament and its sphtting into a 







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m^' 



of roof-iowin?tub°e?cle*s"'"7':''Rofrha?r aS'tt^T '^^r'T""""^' '■ G^^^' ^'^ 

 Cross-section of root at 6 tecterial tissue 1ft r 11 f ''i'* ^"'"eements at a and e. 25. 

 nucleus at n. 26. Rod and y sUed or^^'unS fr„™ ?«"" P'^"*, fi"=d with the organism 

 containing bacterioids. After Frank "^^"'™' ^■^'"" 30 more enlarged. 31. Single cell 



