THE DECOMPOSITION OF CELLULOSE IN SOILS 467 



III. Biochemical Features. 



12. Dunham's solution, 10 days. No ammonia formed; nitrite formed. 



13. Starch nitrate solution, 10 days. No ammonia formed; no nitrite 



formed. 



14. Peptone nitrite solution, 10 days. No indol formed. 



15. Carbohydrate broths, 12 days. No gas produced. Per cent of acidity 



(Fuller's Scale) with: Dextrose, .30; Lactose, .10; Saccharose, 

 .00; Maltose, .20; Glycerine, .00; Mannite, .00; Starch, .30. 



Pseudomonas minuscula, n. sp. 



Soukce: Soil from Bonita, California; Lordsburg, California; and Sanger, Cali- 

 fornia. 

 I. Morphology. 



1. Vegetative cells : Average dimensions, .9 x .5 fx. 



2. Endospores : None observed. 



3. Flagella : 1, rarely 2 in number ; 3 to 4 yu, in length. 



4. Staining reactions : Gram positive. Stains readily with the aniline 



dyes. 

 n. Cultural Characteristics. 



5. Agar strokes, 5 days. 



Beef agar: Moderate, flat, grayish white, filiform growth. 



Potato agar: Abundant, moist, glistening, grayish to yellowish white. 



Peptone starch agar: Moderate, grayish white, filiform growth. 



6. Potato cylinders: No apparent growth after 30 days, but potato is 



bleached along the track of the inoculating needle. 



7. Gelatin stab: Moderate growth at surface and alone track of needle 



in 6 days ; slight napiform liquefaction after 30 days. 



8. Beef broth, 5 days : Turbid. 



9. Litmus milk: Reddened in 6 days; neither coagulated nor digested in 



30 days. 

 10. Plate cultures. 



Ammonia cellulose agar, 15 days. 



Form : Round or irregularly round. 



Size : Surface colonies 1 to 2 mm. ; bottom colonies may attain a 



diameter of 6 to 10 mm. 

 Enzymic zone : 1.5 to 2 mm. 

 Elevation : Slightly depressed. 

 Consistency : Soft. 

 Chromogenesis : Nucleus and rim are white, remainder of colony 



grayish white. 

 Internal structure: Granular. 

 Edge : Undulate. 

 Peptone cellulose agar, 15 days. 



Form : Round or irregularly round. 



Size: 1 to 2 mm. ; bottom colonies frequently attain a diameter of 



10 mm. 

 Enzymic zone: 1 to 1.50 mm. 

 Elevation: SHghtly convex. 

 Consistency : Soft. 



Chromogenesis : White to grayish white. 

 Internal structure: Granular. 

 Ejdge : Erose. 



