26 AGRICULTURAL BACTERIOLOGY 



2. Cells motile: 



a. "With polar llagella Pseudomonas 



b. With peritrichoiis (lamella Bacillus 



Family III. Spirillacece. Cells elongated and bent, usually spirals 



or segments of spirals. 



1. Cells non-motile Spirosoma 



2. Cells motile: 



a. Cells short, comma-shaped, one to three polar fla- 



gella Microspira 



&. Cells longer, with tuft of polar flagella Spirillum 



c. Cells very long and slender, flexible. Flagella, if pres- 



ent, demonstrated only with difficulty Spirochceta 



Suborder II. Trichobacteria. (Family Chlamydobacteriacece) 



Cells cylindrical, united in threads or filaments, surrounded 

 by a sheath. 



a. Filaments untranched Leptothrix 



6. Filaments showing false branching Cladothrix 



c. Filaments showing true branching: 



1. Spores produced Nocardia 



2. No spores observed Actinomyces 



The terms applied to specific organisms have various 

 meanings. Usually thev refer to the type of decomposi- 

 tion caused by the organism, the disease produced by it, 

 its habitat, or its respective group morphologically Ex- 

 amples are as follows: Bact. lactis acidi, a non-motile rod 

 that produces lactic acid as its chief by-product ; B. typho- 

 sus, a motile rod causing typhoid fever ; B. coli communis, a 

 motile rod the habitat of which is that part of the digestive 

 tract known as the colon; B. Welchii, a motile rod named 

 from its discoverer, Dr. William Welch, one of the most 

 prominent of American bacteriologists. 



The subjects of classification and nomenclature in bacter- 

 iology are much confused. The same organism may be 

 described and referred to in the literature under many 

 names. 



Morphology of yeasts. The yeasts, or saccharomycetes, 

 as they are freqently called because of their growth in sugar 

 solutions, are unicellular organisms like the true bacteria, 



