1002 MANUAL OF DETERMINATIVE BACTERIOLOGY 



APPENDIX TO ORDER CHLAMYDOBACTERIALES 



A recently recognized order of filamentous bacteria includes organisms similar in 

 many ways to those included in Chlamydohactcriahs. 



ORDER CARYOPHANALES PESHKOFF.* 



fJour. Gen. Biol., (Russian), 1, 1940, 611, 616.) 



Filamentous or bacillary bacteria of variable size characterized either by the pres- 

 ence of a central body or a ring-like nucleus which frequently takes the form of a disk. 

 The.se bodies are clearly visible in the living cells. The nuclear elements give a clear- 

 cut Feulgen reaction. The filaments may be enclosed in a sheath. Colorless. The 

 individuals consist of cylindrical cells enclcsed in a continuous sheath or they are 

 tube-like coenocytic organisms containing varying numbers of ring or disk-like nuclei 

 separated from each other by alternating protoplasmic segments. These may disin- 

 tegrate into mononucleate coccoid cells. Gonidia sometimes formed. Found in water 

 and in the intestines of arthropods and vertebrates. 



FAMILY I. POXTOTHRICACEAE PESHKOFF. 



Jour. Gen. Biol. (Russian), 1, 1940, 611, 616.) 



Long, unbranched filaments which consist of separate cells in a continuous sheath. 

 Multiplication by cell division, homogoniaand unicellular gonidia. Resemble the blue 

 green algae but they are non-motile and photosynthetic jiigments are lacking. Free 

 living forms. 



Genus I. Pontothrix Nadson and Krassilnikov. 



(Comp. rend. Acad. Sci. de U.R.S.S., A, Xo. 1, 1932, 243-247.) 



Characters as for the familJ^ 



The type species is Ponlolhrix longisshna (Molish) Xadson and Krassilnikow. 



1. Pontothrix longissima (Molish) ments, 1.5 to 2.0 by 1.0 to 5.0 microns. 



Nadson and Krassilnikow. {Chlaniy- Filaments 0.5 cm in length. Cells show 



doi/irz.r Zo7i(7zsszwa Molish, Cent. f. Bakt., a central chromatin body. Found on 



II Abt., 33, 1912, 60; Nadson and Krassil- Zoslcra marina in the Bay at Sebastopol 



nikow, loc. cit., 243.) Cells in the fila- on the Black Sea. 



FAMILY II. ARTHROMITACEAE PESHKOIT. 

 (Jour. Gen. Biol. (Russian), 1, 1940, 611, 616.) 



Filaments probably divided into cells although septa (protoplasmic?) disappear 

 during sporulation. Disk-like nuclei alternate with thin protoplasmic segments 

 (septa). Spores form in the distal ends of filaments. Non-motile. The filaments 

 are attached by a spherical body in groups to the intestinal wall of insects, crusta- 

 ceans and tadpoles. 



Genus I. Arthromitus Lady. 

 (Proc. Acad. Nat. Sci., Philadelphia, 4, 1849, 227.) 

 Characters as for the family. Although the description is worded somewhat 

 differently, there does not seem to be any essential difference between this and the 

 following genus. 



The tj'pe species is Arthroniilus crisiatus Leidj'. 



* Arranged by Prof. Michael A. Peshkoff, Institute of Cytology, .\cad. of Sci., 

 Moscow, U.S.S.'R., April, 1947. 



