TYPHOID INOCULATION IN ANIMALS. 299 



out in absolute alcohol, and cleared up in xylol and 

 mounted in balsam, the bacilli (particularly if the tissue 

 is the liver or spleen) can readily be detected massed 

 together in their characteristic clumps. If used in the 

 same way, the alkaline methylene-blue solution gives 

 also very satisfactory results. 



In searching for the typhoid bacilli in tissues, their 

 mode of growth under these circumstances must always 

 be borne in mind, otherwise much labor will be ex- 

 pended in vain. In tissues the typhoid bacilli do not 

 lie scattered about in the same way as do the organisms 

 in tissues from cases of septicaemia ; they are not 

 regularly distributed along the course of the capillaries, 

 but are localized in small clumps through the tissues, 

 and it is for these clumps, which are easily detected 

 under the low-power objective, that one should search. 

 When the section is prepared for examination, if it be 

 gone over with the low-power objective, one will notice 

 at irregular intervals little masses that look in every 

 respect like particles of staining-matter which have been 

 precipitated upon the section at that point. When these 

 little masses are examined with a higher power objective 

 they will be found to consist of small ovals or short 

 rods so closely packed together that the individuals 

 composing the clump can often be seen only at the very 

 periphery of the mass. This is the characteristic ap- 

 pearance of the typhoid organism in tissues. The little 

 masses are usually in the neighborhood of a capillary. 



Eesult op Inoculation into Lower Animals. — 

 A great many experiments have been made with the 

 view of reproducing the pathological conditions of this 

 disease, as seen in man, in the tissues of lower animals, 

 but with limited success. Fatal results without the 



