GENERAL SYSTEMATIC BACTERIOLOGY 27 



bb. Somalia associated into colonies through intercellular mucxxs. 



Unbranched Subtribe II. Myconostoceae 



c. Somalia cylindric, slender, implicate, twisted, invested in mucus, 

 in globular colony . . . .Genus 15. Myconostoc 

 bbb. Somalia free, pseudoramose. 



Subtribe III. Cladothriceae 

 c. Somalia cylindric, leptothrichoid, lower portion scarcely articu- 

 late, slender, straight or slightly bent, pseudo-dicholomous. 

 Microgonidia formed by a series of successive longitudinal and 

 transverse divisions, globose, in a pseudo-sporangium, escaping 

 laterally and developing new Somalia. 



Genus 16. Cladothrix 

 cc. Somalia cylindric, leptothrichoid, indistinctly articulate, slender, 

 straight or slender spirals, sparsely branched. 

 Genus 17. Streptothrix 



Luerssen (1879) in the first volume of his Botanik discusses the genera 

 of bacteria. Those recognized by him may be differentiated as follows : 



Luerssen's Classification of Bacteria (1879) 



a. Cells not united in filaments, after division quickly falling apart or remain- 

 ing in pairs, free or united into colonies by mucus, 

 b. Cells divide in one plane. 



c. Cells spherical 1. Micrococcus 



cc. Cells ellipsoidal or short ellipsoidal 



2. Bacterium 

 bb. Cells dividing regularly in three directions of space forming cubical 



packets 3. Sarcina 



aa. Cells in cylindrical threads. 



b. Filaments straight, indefinitely jointed. 



c. Filaments very slender and short, rod shaped. 



4. Bacillus 

 cc. Filaments very slender and long. . . .5. Leptothrix 



ccc. Filaments thick and long 6. Beggiatoa 



bb. Filaments wavy or spiral. 

 c. Short and stiff. 



1. Filaments slightly curved 7. Vibrio 



2. Filaments spiral 8. Spirillum 



cc. Long, flexuous 9. Spirochaete 



Duclaux (1879-80) in his extensive "Memoire sur lelait" described 

 with the generic name Tyrothriz a considerable number of organisms 

 isolated from milk and cheese. The species are not closely related, 

 and the group decidedly heterogeneous, the name in consequence has 

 been but little used. The same may be said of the generic name 

 AcHnohacter (species A. polymorphum which he isolated from milk). 



Winter (1880) published in the volume "Die Pilze" of Rabenhorst's 

 Kryptogamen-flora one of the most extensive classifications made up to 

 this time. The key to the genera follows : 



