40 



Part III. — Twenty -eighth Annual Report 



The yellowish to orange-coloured colonies gave the following results : — 



In the gelatine stab cultures a thin streak of growth was visible after 24 

 hours, aud by 36 hours liquefaction of the gelatine was seen commencing 

 round the growth on the upper surface of the tube. Liquefaction proceeded 

 rapidly, and the growth gradually fell to the bottom of the tube as a 

 flocculent deposit, and appearing of a bright yellow colour. 



The stroke cultures on the Agar tubes showed an abundant shiny opaque 

 growth in 24 hours, generally passing from a faint orange to a yellowish colour. 



Litmus Peptone Milk. — This medium was turned acid, shown by the 

 disappearance of the blue colour and appearance of red colour. The milk 

 was also distinctly coagulated. 



Bouillon. — In this medium there appeared at first a uniform turbidity 

 which gradually settled to the bottom of the tube, showing a yellowish tint. 



Potato Medium. — In 48 hours there was an abundant growth of a distinctly 

 orange colour. 



Microscopical Examination of Sub-cultures. 



They all showed the presence of cocci varying from -7/x to '9fi in diameter, 

 spherical in shape, and the growths occurred in irregular groups or masses. 

 The cocci were strongly gram positive, and stained with all the ordinary basic 

 aniline dyes. These cocci exhibited all the essential biological, cultural, 

 and microscopic characters of the staphlococcus pyogenes aureus. 



Examination of the Sub-cultures of other Colonies. 



These were all examined after 48 hours' growth. 



Gelatine Stab Cultures— Thin, whitish streak of growth ; no liquefaction 



of gelatine, and after 8 days a few bubbles of gas in the media. 

 Agar Stroke Cultures — A thin whitish-opaque line of growth. 

 Litmus Milk — Medium turned acid and milk clotted. 

 Bouillon — Slight turbidity. 



Potatoes — A thin film of growth, moist-looking, and of brownish tint. 

 Microscopic Examination. 



These colonies were seen to be short, rod-shaped bacilli, varying from 0'3/x 

 to 0-7/x in diameter. They stained with basic dyes, but very readily 

 decolorised by Gram's stain. 



Hanging drop preparations were then made, and the bacilli were found to 

 be motile, with generally a slow rotatory motion. 



The following media were then inoculated and incubated at 37 Z C. : — 

 L MacConkey's Bile Salt Glucose Peptone Litmus Solution. 

 II. Drigal-ki and Conradi's Nutrose Litmus Agar. 

 III. Neutral-Red Bile Salt Agar. 

 After 48 hours' growth : — 



I. Showed the presence of acid and gas. 

 II. Numerous red colonies. 



III. Numerous red colonies colouring the surrounding medium red, and 

 producing a characteristic haze. 

 From the colonies on media II. and III. sub-cultures were nade on the 

 following media and incubated at 37 C. : — 



A. Glucose Neutral Red. Broth. 



B. Lactose Peptone Litmus Solution. 



C. Peptone Water. 



D. Litmus Milk. 



After 48 hours A. showed greenish-yellow Fluorescence . . FL. 



After 48 hours B. „ Acid and Gas AG. 



After 6 days C. „ Indol production IN. 



After 4 days D. „ Acid and Clot AC. 



