350 THALLOPHYTES 



and partly by the movements of animals with which they are 

 associated. Their structural simplicity, power of resistance, and 

 gelatinization of walls suggest a relationship to the Blue-green 

 Algae. 



In connection with Bacteria another group of organisms, known 

 as the Myxobacteria, is commonly discussed. As the name sug- 

 gests, the myxobacteria resemble both the Bacteria and Myxo- 

 cytes. They differ from the Bacteria in that they form colonies, 

 which in some cases are definite and elaborate in form. Some 

 form colonies resembling a stalk bearing a group of sporangia at 

 its summit. The life histories of the individuals of a colony are 

 essentially the same as those of the Bacteria, differing chiefly in 

 that the resting cells or spores form rod-like cells which escape 

 and assemble to organize the colony. 



