MA LARIA. 



227 



exuding drop, touch the top of the next drop with a clean 

 cover-glass held with forceps, being careful to avoid touching 

 the skin, and taking the drop when small, so that the corpus- 

 cles will be spread out in a uniform layer, not in rouleaux, 

 when the cover-glass is laid on the slide ; press the cover- 

 glass on to the slide gently ; if the cover-glass and slide are 

 clean, the blood will spread in 

 an even thin layer; examine 

 with a y^ oil immersion. Prep- 

 arations made in this way will 

 show, if examined immediately, 

 the amoeboid plasmodium in- 

 side of the red blood-cells, being 

 especially recognizable by the 

 movements or the contained 

 pigment. It is possible some- 

 times to keep such preparations 

 for several hours. 



When examination of fresh 

 blood is not practicable, or 

 when it is desired to preserve 

 the preparation, resort to the 

 procedure of staining must be 

 had. This is best accomplished 

 by the methylene-blue and eosin 

 methods, either applied to- 

 gether, or each dye being used 

 separately, as follows : 



A drop of blood is taken as 

 just described, spread evenly 

 upon a thin cover-glass, and 

 allowed to air-dry ; the film 

 is then set by immersing the 

 cover-glass for twenty to thirty minutes in a mixture of equai 

 parts of absolute alcohol and ether ; after drying, the mixed 

 stain (methylene-blue and eosin) is applied over the surface 

 of the. film and allowed to remain for five minutes ; it is then 

 poured off, the preparation washed thoroughly in distilled 



Quotidian sestivo-autumnal mala- 

 rial plasmodium : 1-4, Hyaline ring 

 forms ; some cells show infection with 

 more than one organism; 5-7, pig- 

 mented forms ; in 6 one hyaline form ; 

 8, segmenting forms ; segmentation 

 complete within infected red blood- 

 corpuscle ; 9, flagellate form (microga- 

 metocyte); 10, 11, 13, 15, crescentic 

 forms ; 12, ovoid form ; 14, nou-flagel- 

 late forms (macrogamete). 



