M 



PLATE 18. 

 Bacterium coli (Escherich). L. and N. 



I. Gelatin stab culture, ten days at 22°. 

 II. Gelatin streak culture, four days at 22°. In nature 

 is transparent, resembling mother-of-pearl in iridescence. 

 Compare also Plate 16, vi. 



III. Agar streak culture, four days at 22°. Compare 

 also Plate 16, v. 



IV. Agar stab culture, two days at 22°. Stab canal. 



V. Agar stab culture, two days at 22°. Surface 

 growth. 



VI. Agar plate, four days at 22°. X 60. Deep colo- 

 nies. Compare also Plate 14, vi. 



VII. Agar plate, four days at 22°. X 60. Part of a 

 superficial colony. May also occasionally present forms 

 like the bacillus acidi lactici. Compare Plate 12, iv; Plate 

 14, vi ; Plate 17, vi. 

 VIII. Agar plate, three days at 22°. Natural size. 

 IX. Potato culture, five days at 22°. May also be 

 paler or more deeply colored. 



X. Bacteria with long flagella of Bacterium brassiere 

 acidce. X 1000. Stained according to Loffler. 



XI. Bacterium of pigeon diphtheria surrounded by fla- 

 gella. X 1000. Stained according to Loffler. 



XII. Bacteria urith one flagellum, rarely two flagella, of 

 Bad. coli /3 unipolaris. X 1000. Stained according to 

 Loffler. 



^ JV 



X. XI. XII. 



