of both groups so far described have been found in fresh and salt water, soil and decomposing organic matter, especially dung. Not as above; cells non-motile or motile, when free in solutioia, by means of flagella; proceed to Section G p. 1008 21. Cells which, on rabbit dung or bacterial cell agar or other suitable media, produce spherical or rod-shaped microcysts either lying free among the rods or l)orne in macro- scopically visible fruiting bodies formed by transformation of whole or part of the population of rod-shaped cells; cells rarely more than 10 microns long; proceed to Manual keys for the order Myxobacterales p. 858 Not as above 22 22. Rod-shaped cells forming articulated chains Bactoscilla p. 848 Not as above 23 23. Filaments from 12 to 100 microns or more in length, highly flexible and actively motile by gliding motion; cells may bend and wave but do not rotate Microscilla p. 849 Not as above 24 24. Cells usually less than 12 microns long. Two groups are possibly represented here: If the colonies are pigmented yellow, pink, green, orange or black, they probably belong to the genus Cytophaga p. 858 If they are white and albuminous, they may belong to Soriano's genus Flexibacter p. 858
