1889.] MICROSCOPICAL JOURNAL. 135 



BACTERIOLOGY. 



.The Bacillus of Leprosy.* — The bacillus of leprosy is met with 

 as a fine rod-shaped bacillus, rounded or slightly pointed at the ex- 

 tremities, and averaging about 5 micromillimeters in length by a little 

 less than i micromillimeter in diameter, v'^ome individual bacilli may 

 be observed with bright oval spores, and manv. though not all. present 

 an active to-and-fro motion. In quite a number of specimens studied 

 there w^as a beaded appearance, owing to the local centralization of pro- 

 toplasmic masses. 



The bacilli are found most abundantly in the leprous nodules of the 

 skin, in which they literally swarm, appearing in some portions almost 

 as plentiful as the cells of the tissue itself. They are also very plentiful 

 in the leprous lesions of the buccal, laryngial, and other cavities of the 

 body. Some bacilli are found in the internal organs, as the kidneys, 

 liver, spleen, and lymphatic system. 



There are several good methods of staining Bacillus leprae ^ but that 

 which was found to be the most satisfactory for the cover-glass prepar- 

 ations is the acid solution of eosin-hcematoxylin of Ehrlich. Sections 

 also may be stained in this manner ; but the method of Babes is more 

 satisfactory. It consists in first staining with a solution of rosaniline 

 hydrochlorate in aniline water. Then bleach w^ith a solution of hydro- 

 chloric acid in water (i to 4), afterwards re-staining Avith methylene 

 blue. 



Observations of the Mode of Growth of Bacillus Leprae. — A 

 cover-glass in the centre of wliicli hatl been deposited a drop of steril- 

 ized blood serum inoculated with the bacilli was placed, culture down- 

 ward, on a cell slide. The latter was made by cementing a glass ring 

 to the centre of a glass slip, making, w'ith the cover-glass, a closed cell, 

 in the bottom of which was placed a drop of water to maintain the 

 moisture of the culture. The cover-glass was sealed in its position on 

 the top of the glass ring with olive oil, as it is not necessary to admit 

 air, the spores germinating freely independent of its admission. The 

 whole, prepared in this manner, was placed on the stage and all of that 

 portion of the microscope below the focusing apparatus was enclosed 

 in a box kept .at a temperature of about 100° F. This arrangement af- 

 forded the means of observing everything taking place in the culture 

 thus placed immediately beneath the cover-glass, which latter, being of 

 the ordinary thickness, permitted of the same facility of observation as 

 an ordinary slide preparation. 



From among several preparations a sufficient number wei'e success- 

 ful to show the formation and growth from spore to mature bacillus. 

 The spores would swell, then the sharp outline would fade and become 

 transparent at a certain portion of its circumference. From this spot 

 would appear a faint, pale projection, which would grow in length until 

 it reached the size of the mature organism — the outlines of the original 

 spore entirely disappearing. The new bacillus would divide by fission 

 into two, these into four, and so on ad infiHitum. 



The microscopical character and general morphology of Bacillus 

 leprcc greatly resemble Bacillus tuberculosis. The giant-cells in w hicli 



* Proceedings of the American Society of Microscopists, 1888. Paper of Chevalier Q. Jackson, M. D. 



