PLATE 7. 

 Micrococcus tetragenus. Koch. Graffky. 



I. Agar streak culture, five daj^s at 37°. 

 II. Gelatin stab culture, ten days at 22°. Stab canal. 

 Characteristic nail-head form. 



III. Gelatin stab culture, ten days at 22° ; surface growth. 

 In the reproduction the color has turned out brown, but 

 should be white. 



IV. Agar stab culture, six days at 37°. Surface growth. 

 V. Agar stab culture, six days at 37°. The growth 



along the stab is not always so luxuriant. 



VI. Agar plate, five days at 37°. Natural size. 

 VII. Gelatin plate, eight days at 22°. The colonies are 

 naturally pure white. Natural size. 



VIII. Gelatin plate, eight days at 22°. X 60. The 

 larger colony is superficial ; the smaller, deep. 



IX. Microscopic preparation. From a two-days'-old 

 agar culture. X 800. There are not always found 

 tetrads alone, often also single cocci. 



X. Potato culture, seven days at 37°. 

 XI. Microscopic picture. Tetrads before, during, and 

 after division; highly magnified. 



•• . c* 



• .« 



Us •■• 



XL 



