184 The Microscope. 



ently contains two or more of these bodies, but on staining it is seen 

 that the apparently isolated masses are connected by extremely 

 slender protoplasmic filaments. The index of refi'action of these 

 bodies is almost the same as that of the blood corpulscle which con- 

 tains them, and they are most easily seen when round. The most 

 remarkable thing about them is their amceboid motion. This is 

 readily seen, and takes place with about the same rapidity as the 

 movements of the ordinary fresh-water amoeba. While watching 

 them I have seen them disappear, and then slowly reappear in the 

 corpuscle. This is easily explained by their spreading out in a thin 

 layer, their refraction then being so low that they cannot be dis- 

 tinguished from the surrounding corpuscle. As they contract and 

 become thicker they again become visible. In such cases the ap- 

 pearance of amceboid movements will settle the question. Some 

 care is necessary in collecting the blood. The cover-slip should be 

 clean, a very small amount of blood be placed on it. and applied 

 immediately to the slide. When the amount of blood taken is so 

 large that the corpuscles lie over each other, or when they are in 

 rouleaux, it will be impossible to see the bodies. They are much 

 more readily seen in stained preparations. These are made by 

 drying a thin film of blood on the cover-slip, taking care to have 

 not more than a single layer of corpuscles, heating the cover, and 

 staining with some one of the aniline colors, for which purpose 

 fuchsin or methylene-blue will give the best results. At this early 

 stage of the disease, the bodies are not found in the period of 

 apyrexia, and appear to be most numerous at the height of the 

 algid stage. 



After the patient has had several chills the bodies are found 

 also in the interval, but in greatly less numbers than in the parox- 

 ysms. They are much more easily seen and present numerous 

 difFerences from those just described. The small non-pigmented 

 forms are found, but in addition, large ones which almost or entirely 

 till up the body of the red corpuscle. These large forms are always 

 pigmented, the pigment generally taking the form of minute black 

 rods. It may be irregularly distributed through the body, or 

 collected in a mass at one side. The corpuscles containing these 

 large bodies are generally slightly swollen, and very pale, at times 

 apparently entirely wanting in color. The pigment renders the 

 detection of these bodies a matter of comparative ease. In using 

 the Abbe illuminator, the diaphragm may be thrown out entirely, 

 and only the pigment sought for, and when this is found, the char- 



