346 



APPLIED BACTERIOLOGY 



in the form of small cocci arranged in two, four, and eight 

 elements. Cultural characters : 



Gelatine Plates. — Grows slowly, giving rise to small 

 white colonies. The gelatine is slightly liquefied. 



Gelatine Tubes. — Produces a white expansion. 



Potatoes. — Slow growth, producing a yellowish, white 

 expansion, which is restricted to the line of inoculation. 



Sarcina Lutea. — This organism is found in air, water, etc. 

 It forms large cocci, from 1"5 to 2*5 /u. in diameter, and 

 arranged in twos, fours, and eights, in the usual packet- 

 like form. The organisms are non-motile, and are very 

 easily stained by the usual aniline dyes. Cultural 

 characters : 



Gelatine Plates. — Grows slowly, producing small round 

 yellowish colonies. 



Gelatine Tubes. — A slow-growing yellow expansion is 

 produced, made up of a number of raised protuberances. 

 The gelatine is slowly liquefied. 



Agar-Agar. — A thick chrome-yellow growth spreads over 

 the surface of the medium. 



Potatoes. — Slow growth. The colonies are restricted to 

 the line of inoculation. 



Bacillus Subtilis {Hay bacillus) . — This organism occurs 

 in hay, the air, water, the faeces, etc. It is about 6 /a long 

 by 2 /u. broad, about the same length but somewhat 

 narrower than the anthrax bacillus. The organism grows 

 into long threads, and is very motile, having long flagella. 

 Forms ovoid spores about 1'2 fi long by 0*6 ,«. broad. These 

 spores are very resistant to heat ; they will bear exposure 

 to dry heat of 120° C. for one hour. The bacillus is strictly 

 aerobic. Cultural characters : 



Gelatine Plates. — The colonies become visible in about 

 two days, as small white dots in the depth, whereas on 

 +he surface they show small grayish liquefied circles. 



