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MANUAL OF POISONOUS PLANTS 



BEGGIATOACEAE 



Cells cylindrical, dividing in only one plane, destitute of the sheath, united 

 into threads containing sulphur granules, usually motile by means of the un- 

 dulating membrane. One genus only. 



Fig. 25. Chlamydobacteriaceae and Beggiatoaceae. 1. Beggiatoa alba, s Sulfur gran- 

 ules x 800. 2-4. Cladothrix dichotoma; 2 Caenobium x 350. 3. Part of filament magnified 

 1000 times. 4. Cells with flagellae x 1000. 5. Crenothrix polyspora; a, young threads; b, 

 threads separating into bodies; c, older threads with spores x 1000. Fig. 1, 2, and 5, after 

 Zopf, Fig. 3 and 4 after Migula. 



M YXOB ACTERI A CEAE 



In the vegetative stage these occur as swarming rod-shaped organisms held 

 together by a gelatinous substance secreted by the cells ; they show slow creeping 

 movements. They form cysts in which the spores occur. This very peculiar 



