Explanation of Plate 15. 



BACTERIUM COLI COMMUNE. Escherich. 



I. Gelatin plate, eight days at 22. x60. Coli culti- 

 vated from pus. Deep-seated colonies. Ab- 

 normal shapes. 

 II. Gelatin plate, four days at 22. Natural size. 



III. Gelatin plate, one day at 22. x 90. Superficial 



colony. Vide PL 13, VIII. ; PL 16, VIII. 



IV. Gelatin plate, four days at 22. x 60. Superficial 



colony. Vide PL 16, IX. ; PL 17, I., II. 

 V. Gelatin plate, four days at 22. x60. Deep- 



seated colony. 

 VI. Gelatin plate, ten days at 22. x 90. Superficial 



colony. 

 VII. Gelatin plate, ten days at 22. x 90. Superficial 



colony. 

 VIII. Microscopical preparation. Pure culture from an 



agar plate, x 500. 



IX. Bacteria of various kinds of coli. x 1, 000. Great 

 differences in size. 



IX. 



15 



