Genus IV. Ferribacterium, p. 221.
- aa. Coccoid to rod-shaped cells in masses in a gelatinous capsule. Usually show an irregular arrangement of cells.
Genus V. Sideromonas , p. 222.
- 2. Cells with a thin capsule with a torus.
- a. Torus completely surrounds the cells.
Genus VI. Naumanniella, p. 223.
- aa. Torus open at one pole giving the wall the appearance of a horseshoe.
Genus VII. Ochrobium, p. 225.
II. Non-encapsulated cells which form deposits of iron compounds in the cell wall, on the surface of the cells or in the surrounding medium.
- A. Cells coccoid.
Genus VIII. Siderococcus , p. 225.
- B. Cells rod-shaped.
- 1. Found in neutral or alkaline waters.
Genus IX. Siderobacter , p. 226.
- 2. Found in acid mine wastes.
Genus X. Ferrobacillus, p. 227.
Genus I. Siderocapsa Molisch, 1909.
(Ann. Jard. Bot. Buitenzorg, 2 Sér., Supp. 3, 1909, 29; also see Die Eisenbakterien, Jena, 1910, 11.)
Si.de.ro.cap'sa. Gr. noun siderus iron; L. noun capsa a box; M.L. fem.n. Siderocapsa iron box.
One to many spherical to ellipsoidal, small cells embedded without definite arrangement in a primary capsule. The primary capsules may be surrounded by a large secondary capsule, and these may then be united into larger colonies. Iron compounds are predominantly stored on the surface of the primary capsule, and when a secondary capsule is present, it is also completely covered.
The type species is Siderocapsa treubii Molisch.
Key to the species of genus Siderocapsa.
I. Several cells in each capsule.
- A. Attached forms.
- 1. Cells small; up to 8 in number in each capsule.
1. Siderocapsa treubii.
- 2. Cells larger; up to 100 and more in each capsule.
2. Siderocapsa major.
- B. Plankton forms.
- 1. Primary capsules 3.5 to 9 microns in diameter, each containing 2 to 8 cells.
3. Siderocapsa coronata.
- 2. Primary capsules 10 to 20 microns in diameter, each containing up to 60 or more cells.
4. Siderocapsa eusphaera.
II. Only one cell in each capsule. Cells always small.
- A. Capsules attached.
5. Siderocapsa monoeca.
- B. Capsules form unattached iron floes.
6. Siderocapsa botryoides.
