GENERAL SYSTEMATIC BACTERIOLOGY 423 



Phragmidiothrix. Engler (1882, p. 19) named an organism found on 

 the body of a crustacean {Gammarus locusta) Beggiatoa multiseptata. 

 Later (1883, p. 187), his diagnosis was as follows: 



PhrGgmidiothrix , Engl. Fills rectis vel. leviter fiexuosis, gelatinosis, cellulis 

 brevibus egranulosis. Ph. mulliseptnia Engl. Cellulis brevissimis, saepe dia- 

 metro diversis, multis semel vel pluries septatis. 



Zopf (1883, p. 104) (1885, p. 103) gave the name Phragmidiothrix 

 muUiseptata ascribing the name to Engler. His description is "Faden 

 scheidenlos, successiv Theilungen sehr weit gehend. Zellen schwefel- 

 frei. Wasserbewohner." Fliigge (1886, p. 398) defined the genus as 

 one showing variable growth forms. 



Trevisan (1889, p. 10) included this genus with its single species as 

 the third of his tribe Leptotrichee. 



De Toni and Trevisan place this organism next to the genus Beg- 

 giatoa among the filamentous water bacteria with the following de- 

 scription : 



Filamenta evaginata, articulata, articuli diametro longitudinali brevissimo, 

 simplicia, ubique aequilata, basi affixa. Multiplicatio cellularum articulorum 

 divisione in duas directiones (septis transversis et longitudinalibus in coccos 

 (an sporiferos?) abeuntium. Baculogonidia nulla. 



The species is described as follows: 



Filament is 3-6/n in diameter, articulis diametro longitudinali quadruplo-sextu- 

 plo breviori quam transversali. Hab. in aqua marina, ad Gammarum Locustam 

 aflBxa, in sinu Kulensi Germaniae (Engler). Cocci quamquam adine filamentis 

 matricalibus incluse, hue illuc germinant novaque filamenta procreant, guvam ob 

 rem filamenta primigenia lateraliter ramosa, videntur. 



Hueppe (1891, p. 31) says "Die Faden sind in niedrige Cyhnder- 

 scheiben gegliedert, welche in Halbscheiben, Quadranten und schlies- 

 slich in Kugeln zerf alien." 



Hansgirg (1891, p. 313) concluded Phragmidiothrix should be in- 

 cluded in the genus Crenothrix, for the filaments of Phragmidiothrix 

 multiseptata are not as Engler stated, sheathless, but are enclosed in 

 a thin sheath which in all respects corresponds with that of Crenothrix. 

 He states that a species Crenothrix marina previously named by him 

 (1890, p. 20) is probably Crenothrix multiseptata or even C. foetida 

 (Fiorini-Mazzanti), or C. mucor (Oerstedt). Hansgirg concludes that 

 the genus Crenothrix Cohn may be divided into two sections, Phrag- 

 midiothrix including the marine forms with C. foetida as the type and 

 Eucrenothrix with fresh water forms and C Kuhniana as the type. 



