PARASITIC AMOEBJE OF MAN. 



in Balantidium coli just prior to encystment, and 

 also to the whirling motion of Paramceba hominis, a 

 species of amoebae parasitic in man, in which encyst- 

 ment is always preceded by this form of motility. 

 However, in the case of Entamoeba Jdstolytica I have 

 never observed any evidence of encystment, although 

 such organisms have been watched for hours. In 

 addition, progressive motion may be resumed after 

 this form of motility has occurred, thus indicating that 

 it has nothing to do with encystment. 



STAINED PREPARATIONS. This species of amoebae 

 may be stained with any of the methods which have 

 been described, the preparations having been either 

 wet- or dry-fixed. The best results are obtained with 

 Wright's stain, using wet-fixed preparations or with 

 iron hsematoxylin preparations which have been fixed 

 while wet. It is always difficult to stain these para- 

 sites and many preparations will have to be examined 

 before one can expect to obtain material for a careful 

 morphological study. I have found that Wright's 

 stain gives good results and that with it one is able 

 to follow the changes that occur in the nucleus during 

 reproduction. 



It is also possible with this stain to differentiate 

 this species from Entamoeba coli, the larger parasites 

 being differentiated by the deep blue staining of the 

 ectoplasm and the dim staining of the endoplasm, the 



