Micrococcus luteus.

PLATE 6.

Ferd. Cohn, emended by Lehm.

and Neum.

I. Gelatin stab, six days at 22°.

II. Gelatin plate, three days at 22°. X 50. To the left, superficial; to the right, a deep colony.

III. Microscopic preparation. × 1000. From a twodays'-old agar plate. Often the micrococci are grouped in tetrads.

IV. Agar plate, five days at 22°. Natural size. The colonies are sometimes more yellow.

V. Potato culture, six days at 22°. Sometimes it has a dull luster.

Sarcina pulmonum. Virchow. Hauser.

(Pulmonary Sarcina.)

VI. Gelatin stab, twenty days at 22°. The stab is in reality more gray.

VII. Agar streak, twenty days at 22°.

VIII. Gelatin plate, twenty days at 22°. To the left, a superficial; to the right, a deep colony.

IX. Potato culture, twenty days at 22°.
X. Stained flagella. Highly magnified.

V.

VIII.

IX.