FAMILY GALLIOXELLACEAE 



831 



Genus I. Gallionella Ehrenberg. 



(Ehrenberg, Die Infusionsthierchen, 1838, 166; not Gaillonella Bory de St. Vincent, 

 Diet. Classique d'Hist. Nat., 4, 1823, 393; Gloeotila Kiitzing, Phycologia Generalis, 

 1843, 245; Didymohelix Griffith, Ann. Mag. Nat. Hist., Ser. 2, 12, 1853, 438; Spiro- 

 phyllumEllis, Cent. f. Bakt., II Abt., 19, 1907, 502; Nodofolium Ellis, Proc. Roy. Soc. 

 Edinburgh, 28, Part 5, 1908, 339.) From an incorrect spelling of the algal genus 

 name, Gaillonella. 



Description as for the family. 



The type species is Gallionella ferruginea Ehrenberg. 



Key to the species of genus Gallionella. 



I. Cells kidney-shaped; stalks branched. 



A. Stalks slender, spirally twisted. 



1. Cells small, stalks very slender. 



1. Gallionella ferruginea. 



2. Cells larger, stalks broader. 



2. Gallionella major. 



B. Stalks thick, not definitely in spirals. 



3. Gallionella minor. 

 II. Cells oval or round; stalks unbranched. 



4. Gallionella comeola. 



1. Gallionella ferruginea Ehrenberg. 

 (Gaillonella ferruginea Ehrenberg, Vorl. 

 Mittheil. ii. d. wirkl. Vorkommenn fossi- 

 ler Infusionen u. ihre grosse Verbreitung, 

 Ann. Phys., Ser. 2, 8, 1836, 217; Ehren- 

 berg, Die Infusionsthierchen, 1838, 166; 

 Melosira ochracea Ralfs, Ann. and Mag. 

 Nat. His., Ser. 1, 12, 1843, 351 (quoted 

 from Buchanan, General Systematic 

 Bacteriology, 1925, 363); Gloeotila ferru- 

 ginea Kiitzing, Species Algarum, 1849, 

 363; Didymohelix ferruginea Griffith, 

 Ann. Mag. Nat. Hist., Ser. 2, 12, 1853, 

 438; Gloeosphaera ferruginia Rabenhorst, 

 Alg. Mitteleur., no. 387; Hedwigia, 8, 

 no. 9, 1854, 43; Melosira minutula Breb., 

 Alg. Fal., 5, 42 (quoted from DeToni 

 and Trevisan, see below) ; Spirulina 

 ferruginea Kirchner, Algen, Kryptoga- 

 menflora v. Schlesien, 2, 1, 1878, 250; 

 Spirochaete ferruginea Hansgirg, Oestr. 

 botan. Ztschr., no. 7-8, 1888, 5; Spiril- 

 lum ferrugineum DeToni and Trevisan, 

 in Saccardo, Sylloge Fungorum, 8, 1889, 

 1007; Chlamydothrix ferruginea Migula, 

 Syst. d. Bakt., 2, 1900, 1031; Spirophyl- 

 lum ferrugineum Ellis, Cent. f. Bakt., 



II Abt., 19, 1907, 502; Spirophyllum 

 tenue, Nodofolium ferrugineum, Spiro- 

 sotna ferrugineum and Spirosoma sole- 

 noide Ellis, Proc. Roy. Soc. Edinburgh, 

 28, Part 5, 1908, 341; also see Cent. f. 

 Bakt., II Abt., 26, 1910, 321; Gallionella 

 taeniata Enderlein, Bakterien-Cyclo- 

 genie, Berlin and Leipzig, 1925, 252.) 

 From hatin ferruginus, iron rust. 



Kidnej'-shaped bacteria, the cells 0.5 

 by 1.2 microns, which secrete colloidal 

 ferric hydroxide from the concave por- 

 tion of the cell, forming band-like stalks. 

 A rotatory motion of the cells gives rise 

 to a spiral twisting of the stalks. 



In the older studies, the stalks were 

 described 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. 



Habitat: Cool springs and brooks 

 which carry reduced iron in solution. 



