270 



OEDER 11. CHLAMYDOBACTERIALES 



length; including the sheath, they measure 

 1.5 to 1.7 microns in diameter. Several tri- 

 chomes arising from the same point and 

 each trichome developing a few false 

 branches produces a fan-shaped appearance. 

 All trichomes end at approximately the 

 same distance from the starting point. The 

 trichomes are bent so that the entire fan- 

 shaped group arches somewhat. The indi- 

 vidual cells are rod-shaped, 0.5 by 3.0 mi- 



crons. Iron oxide is deposited in the sheath. 

 Around this, a gelatinous mass is formed, 

 as much as 22 microns in length and ovoid in 

 form. Iron is not deposited in this gelatinous 

 mass. 



Source: Found on slides submerged in an 

 aquarium in Berlin in which Cahomba was 

 growing. 



Habitat : Found in fresh water. 



F.\]VIILY II. PELOPLOCACEAE BEGER, Fam. Nov. 



Pe.lo.plo.ca'ce.ae. M.L. fem.n. Peloploca tj-pe genus of the family; -aceae ending to de- 

 note a family; M.L. fem.pl.n. Peloplocaceae the Peloploca family. 



Long, unbranched trichomes usually enclosed in a thin, delicate sheath. Cells within the 

 trichomes, when in the living state, contain false vacuoles which are easily discerned by a 

 reddish gleam of light which they emit; the cytoplasm of the cell appears bluish white. Gen- 

 erally non-motile, but motile species may occur. Reproduction is by transverse fission of the 

 cells. Unattached forms found in fresh-water ponds with decomposing algae. 



Key to the genera of family Peloplocaceae, 



I. Trichomes lie parallel to each other in bundles or bands. 



Genus I. Peloploca, p. 270. 



II. Trichomes occur singh\ 



Genus II. Pelonema, p. 271. 



Genus I. Peloploca Lauterborn, 1913. 

 (Allgem. bot. Ztschr., 19, 1913, 99.) 



Pe.lo'plo.ca. Gr. adj. pellos or pelos dark-colored; Gr. noun place a twining, a braid or a 

 twist; M.L. fem.n. Peloploca dark-colored braid or twist. 



Trichomes of cylindrical, colorless cells with no evident sheath. Occur as motionless 

 bundles or bands. Cells contain false vacuoles which emit a reddish gleam of light. Non- 

 motile. Occur in fresh-water ponds where Char a sp. is undergoing decomposition. Frequently 

 overlooked because the trichomes resemble plant fibers. 



The type species is Peloploca undiilata Lauterborn. 



1. Peloploca undulata Lauterborn, 

 1913. (Allgem. bot. Ztschr., 19, 1913, 99.) 



un.du.la'ta. L. adj. undulatus undulated, 

 with waves. 



Cells 6 to 10 microns long. The trichomes 

 are spirally twisted into wavy bundles that 

 are tightly wound together. The bundles 

 reach a length of 60 to 150 microns. Non- 

 motile. 



Source : Found in Germany in ponds wliere 

 Chara sp. was growing. 



Habitat: Presumably widelj' distributed 

 in fresh-water ponds. 



2. Peloploca taeniata Lauterborn, 1913. 

 (Allgem. bot. Ztschr., 19, 1913, 99.) 



tae.ni.a'ta. L. adj. taeniatus band-like. 



Cells 3.0 to 4.0 microns long. Trichomes 

 united into rather broad, frequently twisted 

 bands. These may have the appearance of a 

 grating or lattice because of the presence 

 of pseudo vacuoles in the individual cells. 



