BACILLUS MESENTERICUS FUSCUS 447 



Agar-Agar. — A yellowish-white expansion is formed. 

 Potatoes. — A dirty-white layer is formed. 



Bacillus Mesentericus Fuscus. — This organism is found in 

 the air, water, hay, on vegetables, etc. It is a short, motile 

 bacillus, which occurs in twos and fours. It forms small 

 spores. Cultural characters : 



Gelatine Plates. — Forms small round white colonies, 

 which show delicate, thread-like projections. The gelatine 

 is liquefied. 



Gelatine Tubes. — The medium is quickly liquefied in the 

 form of a funnel-like depression ; in the liquefied portion 

 are seen a number of grayish flocculent particles. 



Agar -Agar. — Forms a yellowish-brown expansion. 



Potatoes. — The surface becomes covered with a smooth, 

 yellow expansion, which afterwards becomes wrinkled and 

 brown. 



Bacillus Mesentericus Vulgatus (' Potato Bacillus'). — This 

 organism is found on potatoes and other vegetables, in 

 water, milk, etc. It occurs in the form of short, thick 

 bacilli, often occurring ia threads. It is very motile, and 

 forms large oval resistant spores, which fill the interior of 

 the organism. Cultural characters : 



Gelatine Plates. — Small circular yellowish colonies are 

 produced, which rapidly liquefy the gelatine. 



Gelatine Tubes. — In the depth the growth rapidly lique- 

 fies the gelatine along the inoculation track in the form of 

 a funnel ; when the whole contents of the tube have become 

 liquid, a pellicle forms on the surface. 



Agar-Agar. — A dirty-white expansion is formed. 



Potatoes. — Grows rapidly. At first a moist expansion is 

 formed, which afterwards becomes wrinkled and tough. 



Bacillus of Mouse Septicsemia. — This organism was ob- 

 tained originally in garden earth and from putrefying liquids. 



