GENERAL SYSTEMATIC BACTERIOLOGY 71 



B. Cells spherical Thiococcus 



II. Cells spherical Thiospirillnm 



Key to the Genera of Family IV. Rhodobacteriaceae 



Uses the following genera with the same meanings as Winogradsky or Molisch. 

 Rhodomonas (Chromaiium). 

 Rhabdomonas (Rhabdochromati urn) . 

 Rhododictyon {Thiodictyon). 

 Amoeboinonas {Amocbobacter) . 

 Rhodothece {Thiothece). 

 Rhodopolycoccns (Thiopolycoccus) . 

 Rhodococcus (Thiopedia). 

 Lamprocystis. 

 Rhodocystis (Thiocystis). 

 Rhodocapsa {Thiocapsa). 

 Rhodosarcina {Thiosarcdna). 

 Rhodospirillum ( Th lospirillum) . 



Key to the Genera of Family V. Trichobacteriaceae 



I. Not containing sulfur granules: 



A. Branched (with pseudobranches) Cladothrix 



B. Not Branched 



1. Not spiral: 



a. Not attached Lepfothrix 



b. Attached Crenothrix 



2. Spiral: 



a. Slender and flexuous Spirochaeta 



b. Flattened Spirophyllum 



II. Containing sulfur granules: 



A. Not attached. Motile Beggiatoa 



B. Attached Thiothrix 



Key to the Genera of Family YI. Lximinobacleriaceae 



I. Cells not spiral: 



A. Cells rod-shaped: 



1. Active denitrifiers Denitromonas 



2. Active liquefiers Liquidomonas 



B. Cells spherical: 



1. Liquefying gelatin Liqiiidococcus 



2. Not liquefying gelatin SoUdococcus 



II. Cells bent or spiral Liquidovibrio 



Key to the Genera of Family VII. Reducibacteriaceae 



I. Short spiral. Not liquefying gelatin Solidovibrio 



II. Longer spirals Spirillum 



