112 



ESSENTIALS OF BACTERIOLOGY. 



Fro. 58. 



ing then as little buttons, with a porcelain-like shimmer, the 

 edges smooth. 



Stab Culture. A growth along the needle-track, but on the 

 surface a button-like projection, which gives to the growth the 

 appearance of a nail driven into the gelatine, 

 its head resting on the surface ; therefore 

 such cultures are called " Nail cultures." 

 See Fig. 58. Old cultures are colored brown, 

 and contain bubbles of gas. 



Potato. A yellow, moist layer in a few 

 days at brood-heat. Gas bubbles develop. 



Staining. The ordinary aniline stains. 

 The sections do not take Gram's method ; 

 are therefore not suited for double staining. 

 Capsule. Stained as follows : 

 Cover glasses. 



1. Acetic acid, two minutes. 



2. Allow acetic acid to dry by blowing air 

 upon it through a glass tube. 



3 Saturated, aniline water. Gent, violet, 

 ten seconds. 



4. Rinse in water. Mount in Canada balsam. 

 For Sections. 



Bacillus of Pneumo- 

 nia. Stab Culture. 

 (Nail Culture.) 



cone. ale. gent, violet, 50.0 



1. Stain in warm ^ aqua, 100.0 



acetic acid, 10. 



for 24 hours. M. 



2. Rinse in one per cent, acetic acid. 



3. Alcohol to dehydrate. Mount in balsam. 



The capsule will be found stained a light bine, the bacillus a 

 deep blue. 



Pathogentsis. Animals are not affected unless the culture is 

 injected intrapleura. 



Pneumobacilhis of Frankel. (A. Frankel and Weichselbaum.) 

 Synonyms. Pneumococcus ; Diplococcus of Pneumonia ; Mi- 



