Page:Bergey's manual of determinative bacteriology.djvu/899

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FAMILY IV. POLYANGIACEAE
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Genus II. Synangium Jahn, 1924- (Beitrage zur bot. Protistologie. I, Die Polj^angiden. Geb. Borntraeger, Leipzig, 1924, 79.) Syn.an'gi.um. Gr. pref. syn together; Or. noun ancjium vessel; M.L. neut.n. Synangium vessels together (clustered). Cysts united at the base to form a large disc or rosette which is usually elevated above the substrate on a stalk. The individual cj'^st is equipped with an apical tuft of hairs. The type species is Synangium sessile (Thaxter) Jahn. 1. Synangium sessile (Thaxter, 1904) Jahn, 1924. {Chrondromyces sessilis Thaxter, Bot. Gaz., 37, 1904, 411; Chrondromyces lanuginosus Kofler, Sitzber. d. kais. Akad. wiss. Wien, math.-nat. Klasse, Abt. I, 122, 1913, 861; Chondromyces thaxteri Faull, Bot. Gaz., 62, 1916, 226; Jahn, Beitrage zur bot. Protistologie. I, Die Polyangiden. Geb. Borntraeger, Leipzig, 1924, 79; Synangium lanuginosum Jahn, loc. cit.; Synangium thax- teri Jahn, loc. cit.) ses'si.le. L. adj. sessilis sessile, stalkless. Vegetative cells: Cylindrical rods with blunt ends, 0.9 to 1.0 by 3.0 to 8.0 microns. Fruiting body: The cysts are joined to- gether at their bases to form discoid or spherical clusters containing up to 30 indi- vidual cj'sts, the whole being elevated on a stalk of variable height (up to 1 mm), which is usually unbranched and bears one or two clusters at its tip. Each cyst bears an apical tuft of hairs. The diameter of the cyst clus- ter is highly variable (40 to 250 microns), as is the length of the hairs in the apical tuft (7 to 30 microns). The individual resting cells within the cysts are 2.5 to 6.0 by 0.6 to 1.0 microns. The color of developing fruit- ing bodies is initially white, changing to j'ellow, light pink and eventually orange; the shade is greatly affected by environ- mental factors, notably humidity and tem- perature. Sometimes the cyst clusters give rise to secondary stalks which are much thinner and shorter than the primary ones and which are tipped with smaller clusters. Varieties: Three varieties of this species have been named on the basis of the pres- ence or absence of cyst-bearing stalks: one variety is described as sessile, and another as bearing a stalk of variable height (up to 1 mm) which is usually unbranched; the third variety is intermediate between these two. This differentiation in stalks is highly dependent upon environmental conditions. Cultivation : Grown in laboratory culture on hay (Krzemieniewska and Krzemie- niewski,Bull. Intern. Acad. Pol. Sci.Lettres, No. 1-10, Serie B (I), 1946, 37). Pure cultures not obtained. Source: Originally isolated from decaying wood from Florida (Thaxter, op. cit., 1904, 411). Also found in the dung of herbivores from Canada (Faull, op. cit., 1916, 226) and from Austria (Kofler, op. cit., 1913, 861); from soil in Poland (Krzemieniewska and Krzemieniewski, op. cit., 1946, 37). Habitat : Found on the dung of herbivores and on decaying organic matter in soil. Illustrations: Thaxter {op. cit., 1904, PI. 27, Figs. 14-15), Kofler {op. cit., 1913, PI. I, Figs. 1-3), Faull {op. cit., 1916, Pis. 5 and 6), Jahn {op. cit., 1924, Fig. X, page 80) and Krzemieniewska and Krzemieniewski {op. cit.. Pi. 1, Figs. 1-3). Genus III. Podangium Jahn, 1924. {Cystobacter Schroeter, in Cohn, Kryptogamenfiora v. Schlesien, 3, 1, 1886, 170; Jahn, Beitrage zur bot. Protistologie. I, Die Polyangiden. Geb. Borntraeger, Leipzig, 1924, 80.) Po.dan'gi.um. Gr. noun pus, pedis a foot; Gr. noun angium a vessel; M.L. neut.n. Podangium footed vessel. Cysts chestnut-brown or red-brown, single on a more or less definite, white stalk. The type species is Podangium erectum (Schroeter) Jahn.