Mycobacterium tuberculosis (Koch). Lehm. and
Neum. (Tubercle Bacillus.)

I. Glycerin-agar streak culture, fourteen days at 37°.
II. Glycerin-agar streak culture, forty days at 37°.

III. Potato culture, forty days at 37°.

IV. Colonies of tubercle bacilli from a blood-serum culture. X 700. (Copied after R. Koch, Aetiologie der Tuberkulose. Mitteilungen des Kaiserl. Gesundheitsamt, Bd. 2, Taf. IX, 44.)

V. Culture, upon blood-serum, from a piece of a freshly extirpated scrofulous gland. (Copied like the above, Bd. 2, Taf. ix, 44.)

VI. Giant cell with radially arranged bacilli. From a caseous bronchial gland in a case of miliary tuberculosis. (Copied like above, Bd. 2, Taf. 11, 9.)

VII. Microscopic preparation. Pure culture, stained according to Ziehl. X 1000.

VIII. Branching of tubercle bacilli. (Copied after Hayo Bruns, C. B. XVII, No. 23.)

IX. Microscopic preparation. Sputum, stained according to Ziehl. X 1000.

X. Single bacteria, highly magnified.

X.

Mycobacterium lepræ. (Arm. Hansen.) Lehm. and Neum.

I. Giant cell from a leprous ulcer of the epiglottis. Х about 1000. Stained according to Rusell. (Copied from Seifert and Kahn, Atlas der Histopathologie der Nase, 1875, Taf. 38, Fig. 75 b.)

II. Transverse section of a blood-vessel in a leprous testicle. Bacilli in endothelium and in a white blood-corpuscle. Stained by Gram's method, Bismarck brown, eosin, oil of bergamot. X about 1000. (Copied as No. III, fig. v.) III. Ulnar nerve, longitudinal section, stained like above. (Copied from Lie, pathologische Anatomie der Lepra; Archiv für Dermatologie und Syphilis, Bd. XXIX, 1895, Taf. VI, Fig. VII.)

IV. Smear preparation from nasal mucus. Stained by method for tubercle bacillus. From a preparation of Dr. Dieudonné. X 1000.

Mycobacterium tuberculosis y piscicola. L. and N.

V. Streak culture (glycerin-agar), one month old at 22°. VI. Plate culture (glycerin-agar), ten days at 22°. Natural size. Superficial colonies.

VII. Plate culture (glycerin-agar), six days at 22°. X 60. Superficial colony. The dark shadows and bright lights represent the strong reflection of the cartilaginous colony.

VIII. Potato culture, fourteen days at 22°. Sometimes also more homogeneous upon the surface.

IX. Microscopic preparation. Stained by the method