Streptococcus pyogenes. Rosenbach.
I. Agar streak culture, ten days at 37°.

II. Gelatin stab culture, six days at 22°. So vigorous a growth does not often occur.

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

V. Gelatin plate, six days at 22o.

VI. Gelatin plate, six days at 22°. x 70. Somewhat abnormal form with irregular borders. The larger colonies are superficial; the smaller, deep. VII. Gelatin plate, six days at 22°. X 70. Common

x form. The upper, superficial; the lower, deep.

VIII. Agar plate, eight days at 37°. X 50. Larger colony superficial; smaller colonies, deep.

IX. Microscopic preparation from a two days' bouillon culture at 37° X 700. The individual cocci are usually

. more regularly round.

X. Microscopic preparation from a two days' agar culture. Shorter chains. X 1000.

XI. Microscopic preparation, designated Streptococcus conglomeratus. Smear preparation from the blood of the spleen from a case of scarlatina. Copied from Kurth (Kaiserl. Gesundheitsamt., Bd. vii, cfr. xv, 6 and 8).

XII. Chains of streptococci, before and during division. Highly magnified.

Streptococcus lanceolatus. Gamaleia. (Diplococcus

pneumoniæ A. Fränkel.) (Pneumococcus.)
I. Gelatin stab culture, ten days at 22°.
II. Agar streak culture, four days at 37°.
III. Agar stab culture, four days at 37°. Stab canal.

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

V. Agar plate, three days at 37°. Natural size.

VI. Agar plate, three days at 37° X 50. Superficial colony. The darker colony lies near the surface.

VII. Agar plate, three days at 37°. x 50. Deep colonies.

VIII. Gelatin plate, eight days at 22°. The upper colony is superficial; the lower ones, deep.

IX. Smear preparation from pneumonic sputum. X 1000.

X. Pure culture from a three days' old agar plate. X 1000.

XI. Microscopic preparations: (a) Diplococci as single pairs and in chains. Highly magnified. (6) Diplococci surrounded by gelatinous capsules.

a