3/0 BACTERIOLOGY 



The above characters as given by Migula are referred to his genus Strepto- 

 thrix. The Streptothrix of Cohn includes branched forms entirely dis- 

 tinct from the Streptothrix of Migula. Migula's genus is certainly more 

 closely related to the Leptothrix of Kutsing, and later described by Cohn. 

 Furthermore, the rule of priority would direct that the earlier name, Lc.p- 

 tothrix, should be retained. 



I. Filaments not fixed, but associated in tangled masses. 



1. Leptothrix hyalina (iMigula). 



II. Filaments fixed on a substratum. 



A. Filaments short. 



2. Leptothrix epiphytic a (Migula). 



B. Filaments long. 



3. Leptothrix fluitans (Migula). 



4. Leptothrix gigantea Miller. 



5. Leptothrix innominat a Miller. 



6. Leptcthrix buccalis Miller. 



i. Leptothrix hyalina (Migula) 



Streptothrix hyalina Migula: Die Natiirlichen Pflanzenfam., 1895. 



Filaments 0.6 //. in diameter, forming tangled masses. A sheath is demon- 

 strated with iodine. 

 Habitat. Water. 



2. Leptothrix epiphytica (Migula) 



Streptothrix epiphytica Migula : I.e. 



P'ilaments short, colorless, fixed to algae, etc., with a thick gelatinous sheath. 

 Produce ovoid gonidia. 



3. Leptothrix fluitans (Migula) 



Streptothrix fluitans Migula : I.e. 



Very slender filaments 10 mm. long, with a delicate sheath. Produce spher- 

 ical gonidia, which generally remain glued to the filaments. Found 

 attached to the stems of water plants and wet wood. 



The following species are not sufficiently described as regards their morphol- 

 ogy to determine whether they are true species of this genus, or whether 

 they belong to the Bacteriaceae. 



