Page:Bergey's manual of determinative bacteriology.djvu/284

 ORDER II. CHLAMYDOBACTERIALES BUCHANAN, 1917.

Chla.my.do.bac.te.ri.a'les. M.L. fern. pi. n. Chlamdobacteriaceae type family of the order Chlamydobacteriales; -ales ending to denote an order ; M.L. fern. pi. n. Chlamydobacteriales the Chlamydobacteriaceae order. Colorless, alga-like bacteria which occur in trichomes. May or may not be ensheathed. They may be unbranched or may show false branching. False branching arises from a lateral displacement of the cells of the trichome within the sheath; this gives rise to a new trichome so that the sheath is branched while the trichomes are separate. The sheaths may be composed of an organic matrix impregnated with iron or manganese oxides, or they may be composed of an organic matrix free from these oxides. Gram-negative. Reproduction may be by flagellate swarm spores or by non-motile conidia. Endospores of the type found in Bacillus are never developed. Fresh-water and marine forms.


 * I. Conidia, when formed, are motile by means of a sub-polar tuft of flagella.
 * A. Possesses trichomes in which false branching may occur. Motile swarm cells may be formed.


 * B. Possesses ensheathed, unbranching trichomes which may be very long (0.5 cm). Found in fresh water.


 * II. Non-motile conidia are produced.

Chla.my.do.bac.te.ri.a'ce.ae. Gr. noun chlamys, chlamydis a cloak; Gr. neut.n. bacterium a small rod; -aceae ending to denote a family; M.L. fem.pl.n. Chlmydobacteriaceae the family of the sheathed bacteria.

Bacteria which occur in trichomes and which frequently show false branching. Sheaths, when present, may or may not be impregnated with ferric and/or manganese oxides. Cells divide transversely. Swarm cells, if developed, are usually motile by means of a tuft of flagella. Usually found in fresh water.

I. Trichomes surrounded by sheaths which are usually not impregnated with iron or manganese oxides and which do not dissolve in hydrochloric acid. Large forms, mostly sessile.