FAMILY VI. SIDEROCAPSACEAE 



223 



Slender rods measuring 0.5 by 2.5 microns. 

 Rods, several to many placed irregularly in 

 a gelatinous envelope, form, when old, 

 zoogloea-like masses as much as 7.5 microns 

 in diameter. The rods are surrounded by 

 primary capsules which are impregnated 

 with iron compounds and which later fuse. 



Reported by Dorff (Tabulae Biologicae, 

 16, 1938, 221) to be autotrophic. 



Comment: The characters of the genus 

 Siderocystis, as described by Naumann 

 {loc. cit.), do not seem adequate to distin- 

 guish it from the genus Sideromonas, estab- 

 lished earlier by Cholodny. 



Source: Found in the Aneboda region in 

 Sweden. 



Habitat: Forms deposits on submerged 

 objects in ditch and river waters. 



4. Sideromonas major (Naumann, 1922) 

 Beger, comb. nov. {Siderothece major Nau- 

 mann, Kungl. Svenska Vetenskapsakad. 

 Handl., 62, No. 4, 1922, 17; Siderothece 

 minor Naumann, loc. cit.; Siderocystis 

 minor Naumann, ibid., 43.) 



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



Rods broader than those of Sideromonas 

 vulgaris, 0.5 to nearly 1.5 by 1.0 to 1.5 mi- 

 crons. Each rod is surrounded by a large 

 primary capsule; the capsules later fuse 

 and form a gelatinous envelope in which 

 the cells are irregularly arranged. Form 

 zoogloea-like masses up to 10 microns in 

 diameter. Iron compounds deposited within 

 the capsular substance. 



Possibly autotrophic (Dorff, Talnilae 

 Biologicae, 16, 1938, 221). 



Aerobic. 



Comments: While there are some differ- 

 ences in the sizes of the organisms placed 

 by Naumann in the three different species 

 named above, such differences may, in 

 reality, not be significant: these differences 

 may be due to variations in the nutritive 

 value of the water in which each of the 

 organisms was growing. 



Source: Found in the Aneboda region in 

 Sweden. 



Habitat: Develop concretionary deposits 

 (microscopic particles) on submerged ob- 

 jects in swampy ditch and river waters; 

 also found in wells and pipes in waterworks. 



Genus VI. Naumanniella Dorff, 1934. 

 (Die Eisenorganismen, Pflanzenforschung, Heft 16, 1934, 19.) 



Nau.man.ni.el'la. M.L. dim. ending -ella; M.L. fem.n. Naumanniella named for Einar 

 Naumann, a Swedish limnologist. 



Cells ellipsoidal or rod-shaped with rounded ends, occurring singly or in short chains; 

 the rods may be straight or curved and frequently are constricted in the middle. Each cell 

 is surrounded by a small capsule and a marginal thickening (torus) heavily impregnated 

 with iron and manganese compounds. Gelatinous capsules of the type found in Siderocapsa 

 are absent. Cell division occurs simultaneously with constriction and separation of the 

 torus. The species in this genus have not been cultured. Found at the surface and in or on 

 the bottom mud of iron-bearing water. 



The type species is Naumanniella neuslonica Dorff. 



Key to the species of genus Naumanniella. 



I. Cells rod-shaped. 

 A. Cells occur singly. 



1. Cell diameter greater than 1.2 microns with the torus. 



a. Cells with the torus 1.8 to 3.3 by 4.0 to 10.0 microns. 



1. Naumanniella neustonica. 

 aa. Cells with the torus 1.2 to 1.5 by 3.1 to 3.6 microns. 



2. Naumanniella minor. 



2. Cells 1 by 2 microns with the torus. 



