520 C. A. LAUBACH, J. L. RICE AND W. W. FORD 



Broth. Slight turbidity, no scum, no sediment. 



Peptone. Slight turbidity, no scum, no sediment. 



Potato. No visible growth. 



Milk. Complete decolorization within 24 to 48 hours. Gradual 

 production of acidity and late coagulation, which may appear 

 spontaneously and always occurs if the milk be heated. 



Blood serum. Faint thin white non-spreading growth. No 

 hquefaction. 



Fermentation tubes. Glucose : turbidity in bowl and closed arm. 

 No scum. Reaction acid, appearing in 3 to 4 days. 



Saccharose : appearance the same. Reaction acid. 



Lactose : appearance the same. Reaction acid. 



Thermal death point. Spores destroyed by steaming 15 minutes 

 in the Arnold. Survive 18 pounds pressure in the autoclave. 

 Destroyed by 20 pounds pressure. 



Bacillus pseudotetanicus (Kruse) Migula 1900 



This organism was first described by Kruse in the 3rd edition 

 of Flugge's "Die Mikroorganismen" under the name Bacillus pseu- 

 dotetanicus var. aerohius. It resembled Bacillus tetani in mor- 

 phology and spore-formation but was distinguished from it by its 

 aerobic development, its failure to liquefy and its lack of patho- 

 genicity. Apparently the same organism has been described by 

 Neide (1904) as Bacillus sphaericus. The species here described 

 has the morphological and cultural features given by both Kruse 

 and Neide and under the rules of nomenclature the name given by 

 Migula should be adopted. It was found but once as a contami- 

 nation on an agar plate. 



Morphology. Short thick bacilU with rounded ends occurring as 

 single cells or as two cells end to end. In 24 agar cultures they 

 measure 0.75 by 1.5 to 3 microns. Protoplasm homogeneous. 

 Many of the cells are fusiform, distinctly swollen toward the mid- 

 dle while others are swollen at the ends. On glucose agar the or- 

 ganisms are longer and thicker measuring 1.125 by 1.5 to 4 microns. 

 They show no change in the character of the protoplasm. In older 

 cultiu-es the organisms often form long threads measuring 8 to 15 

 microns in length. (Figures 76 and 77.) 



