Figure 7. A. A colony of Bacillus anthracis was suspended, inactivated, and negatively contrasted with aqueous uranyl acetate, as described for Figure 4. The microorganisms, which grow in long chains, do not have flagella. B. The ubiquitous B. subtilis may also grow as long chains. However, in contrast to B. anthracis, the B. subtilis cells show distinct flagella (arrow). Bar = 2.5 μm.