104 ESSENTIALS OF BACTERIOLOGY 



Form. Short spirals, two or three turns, with pointed ends; 

 it has flagella on the ends. 



Properties. Very motile; does not liquefy gelatin. 



Growth. Very slow; mostly on the surface; best at ordinary 

 temperatures. 



Plates. A growth of rings concentrically arranged, every 

 alternate one being transparent; the furthest one from the 

 center possessing small projections. 



Stab-cultures. Growth mostly on the surface. 



Sarcina. Cocci in cubes or packets of colonies. A great 

 number have been isolated, many producing very beautiful 

 pigments. The majority of them found in the air. 



Sarcina Lutea (Schrbter) . Origin. Air. 



Form. Very large cocci in pairs; tetrads and groups of 

 tetrads. 



Fig. 52. Sarcina ventriculi from stomach-contents (x 53) (Van Valzah 

 and Nisbet). 



Properties. Liquefies gelatin slowly; produces sulphur-yel- 

 low pigment. 



Growth.- Slowly, at various temperatures; strongly aerobic. 



Plates. Small, round, yellow colonies. 



Stab-cultures. Grows more rapidly, the growth being nearly 

 all on the surface, a few separated colonies following the needle- 

 thrust for a short distance. Agar, a very beautiful yellow, 

 along the stroked surface. 



