FAMILY V. CAULOBACTERACEAE 



215 



aa. Cells longer, stalks broader. 



2. Galliunella major. 

 2. Stalks short, thick, not definitely in spirals. 



3. GallioneUa minor. 

 B. Stalks branching in simple or compound umbels. 



4. GallioneUa umbellata. 

 II. Stalks unbranched. 



5. GallioneUa infiircata. 



1. GallioneUa ferruginea Ehrenberg, 

 1836. {Gaillonella ferruginea (sic) Ehrenberg, 

 Vorl. Mittheil. ii. d. wirkl. Vorkommen 

 fossiler Infusionen u. ihre grosse Verbrei- 

 tung, Ann. Phys., Ser. 2, 8, 1836, 217; 

 GallioneUa ferruginea Ehrenberg, Die Infu- 

 sion thierchen, 1838, 166; Didymohelix ferru- 

 ginea Griffith, Ann. Mag. Nat. Hist., Ser. 2, 

 12, 1853, 438.) 



fer.ru.gi'ne.a. L. adj. ferrugineus of the 

 color of iron rust. 



Kidney-shaped cells. The full grown bac- 

 teria are 0.5 to 0.6 by 1.2 to 1.5 microns. The 

 cells secrete colloidal ferric hydroxide from 

 the concave portion of the cell, forming 

 band-like stalks 0.6 to 3.3 microns in width 

 and as much as 200 microns and more in 

 length. A rotatory motion of the cells gives 

 rise to a spiral twisting of the stalks. 



In the older studies, the stalks were de- 

 scribed as the organism, the minute cells at 

 the tip having been dislodged or at least 

 overlooked. The cells lie at the tip of the 

 stalk and multiply by transverse binary 

 fission. This gives rise to a dichotomous 

 branching of the stalks. Stalks become very 

 long and slender, with smooth edges. 



Not cultivated in artificial media. 



Distribution: Usually the branched stalks 

 are attached separately in great numbers to 

 solid surfaces. They may, however, float in 

 irregular floes distributed throughout the 

 water. Less commonly they form balls up 

 to 3.0 microns in diameter. In these the 

 stalks radiate from a center and such groups 

 have been described as Gloeosphaera ferru- 

 ginea Rabenhorst. In a third variety, solid 

 tubercles richly encrusted with ferric com- 

 pounds are formed. These are found in old 

 pipelines or they may occur free in nature. 

 These tubercles have been named Sphaero- 

 fhrix latens Perfiliev. 



Habitat: Found in cool springs and brooks 



which carry reduced iron in solution; also 

 found in wells, in storage basins in water- 

 works and in pipe lines. 



2. GallioneUa major Cholodny, 1927. 

 (Trav. Station, biolog. du Dniepre Acad, 

 des Sci. de I'Ukraine, Classe Sci. Phys. et 

 Math., 3, Livre 4, 1927.) 



ma'jor. L. comp. adj. major larger. 



Very similar to GallioneUa ferruginea, but 

 the cells are distinctly larger (1.0 by 3.0 

 microns). Stalks are 3.0 to 6.0 microns broad. 

 Some cells that fail to divide reach a length 

 of 7 microns or more; these form stalks of 

 double the normal width. 



The cells contain one or more vacuoles, 

 apparently filled with an iron compound. 



Source: Found in springs near Krassnodar 

 (Caucasus). 



Habitat: Found in iron-bearing waters. 



3. GallioneUa minor Cholodny, 1924. 

 (Ber. d. deutsch. Bot. Ges., 42, 1924, 42; also 

 see Cholodny, Die Eisenbakterien, Pflan- 

 zenforschung. Heft 4, 1926, 47.) 



mi 'nor. L. comp. adj. minor smaller. 



Cells as in GallioneUa ferruginea, but 

 stalks are shorter, thicker and more band- 

 like than twisted. After division, cells do not 

 separate as quickly as in GallioneUa ferrii- 

 ginea. The branches gradually become en- 

 crusted until the stalks are quite obscured. 

 Branches of stalks are not more than 20 to 

 30 microns long. 



Source : Found in a small spring near the 

 Biological Station in Dniepre. Also found 

 by Beger (Ber. d. deutsch. Bot. Ges., 62, 

 1944, 11) in material from Camerun in 

 Africa. 



Habitat: Found in iron-bearing waters. 



4. GallioneUa umbellata Beger, 1949. 

 {GallioneUa ferrxiginea Palm, Svensk. Bot. 



