Explanation of Plate 7. 



MICROCOCCUS TETRA GENUS. Koch, Gaffky. 



I. Agar streak culture, five days at 37. 

 II. Gelatin stick culture, ten days at 22. Puncture 

 canal. The " nail-head" shape is characteristic. 



III. Gelatin stick culture, ten days at 22. Surface. 



The color is too brown in the plate ; should have 

 been white. 



IV. Agar stick culture, six days at 37. The puncture 



does not always turn out so vigorous. 

 V. Agar stick culture, six days at 37. Surface. 

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

 VII. Gelatin plate, eight days at 22. In nature the 



colonies are pure white. Natural size. 

 VIII. Gelatin plate, eight days at 22. x60. The larger 

 colony is superficial, the smaller ones are deep. 

 IX. Microscopical preparation from an agar culture 

 (X800) two days old. We do not always find 

 tetrads alone. There are numerous individual 

 cocci. 



X. Potato culture, seven days at 37. 

 XI. Microscopical appearances. Tetrads before, dur- 

 ing, and after division highly magnified. 



XI. 



