456 SOIL SCIENCE 



Enzymic zone : The entire colony is transparent. The enzyme 

 does not clear the cellulose beyond the development of the 

 colony. 



Elevation : Young colonies are saucer-shaped. As the colony 

 spreads the depression is less apparent. 



Chromogenesis : Vitreous. Some colonies show a very narrow white 

 rim. Old colonies frequently become a light transparent yel- 

 low. 



Internal structure : Granular. 



Edge : Entire. 

 Peptone cellulose agar, 15 days. 



Form : Round. 



Size : 10 to 12 mm. in 15 days ; colonies continue to grow as long 

 as the medium is kept moist. When the plate contains only a 

 very few colonies the diameter may be 50 mm. or more in 30 

 days. 



Enzymic zone : The entire colony is transparent with the excep- 

 tion of a very narrow white rim. The enzyme does not 

 spread beyond the development of the colony. 



Elevation : The young colonies are distinctly concave. As the 

 colony becomes older the depression is less apparent. 



Chromogenesis : Vitreous. Some colonies show a very narrow 

 white rim. Old colonies frequently become a light trasparent 

 yellow. 



Internal structure : Indeterminate with the exception of the nar- 

 row white rim which is granular. 



Edge : Entire. 

 Peptone starch agar: No colonies produced in 10 days. 

 Beef agar: No colonies produced in 10 days. 

 Potato agar: No colonies produced in 10 days. 



11. Filter paper broths, 15 days. " The paper is reduced to a very thin yel- 



lowish filmy mass, which disintegrates on very slight agitation. 

 The paper is destroyed at about the same rate with ammonium 

 sulphate, potassium nitrate or peptone as the source of nitrogen. 

 A slower destruction of the paper occurs when nitrogen is sup- 

 plied in the form of casein. 

 III. Biochemical Features. 



12. Dunham's solution, 10 days. No ammonia produced ; no nitrite pro- 



duced. 



13. Starch nitrate solution, 10 days. No ammonia produced ; no nitrite pro- 



duced. 



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



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



(Fuller's Scale) with: Dextrose, 0.00; Lactose, 0.00; Saccharose, 

 0.00 ; Maltose, 0.00 ; Glycerine, 0.00 ; Mannite, 0.00 ; Starch, 0.00. 



Bacillus iugis, n. sp. 



Source : Soil from Lordsburg, California ; Redlands, California ; and San Fer- 

 nando, California. ' 

 I, Morphology. 



1. Vegetative cells : Average dimensions 1.4 x .4 ^. 



2. Endospores : None observed. 



