Explanation of Plate 13. 



BACTERIUM ACIDI LACTICI. Fliigge. 



(Lactic-acid bacillus.) 



I. Gelatin stick culture, five days at 22. In nature 



the puncture canal is a little whiter. 

 II. Agar streak culture, five days at 22. 



III. Agar stick culture, three days at 22. Puncture 



canal. 



IV. Agar stick culture, three days at 22. Surface. 

 V. Agar plate, three days at 22. Natural size. 



VI. Agar plate, three days at 22. x 50. Upper col- 

 ony superficial, lower ones deep seated. Vide 

 PI. 14, VII. 



VII. Gelatin plate, two days at 22. 

 VIII. Gelatin plate, two days at 22. x50. Upper col- 

 ony superficial, lower colonies deep seated. 

 The superficial colony may vary extremely in 

 its growth. Vide PI. 15, IV., VII. ; PI. 16, 

 IX., VIII.; PL 17, I., II. 

 IX. Microscopical preparation. Pure culture from an 



agar colony, x 800. 



X. Potato culture, six days at 22. The air bubbles 

 on the surface often cover it completely. 



13 



