ENTAMCEBA HISTOLYTICA f>03 



tlie names of entamoeba coli and entanm-ba hi&tolytica re- 

 spectively. We shall give the chief points in his description, 

 but it must be kept in view that amcebie of dysentery studied 

 by others present differences in character. To these also refer- 

 ence will be made below. 



l',i>f<iin<i-li<i /tistolytica, as seen in dysenteric stools, occurs in 

 the form of rounded, oval, or pear-shaped cells, measuring 

 12 to r>0 //. in diameter (Fig. 169, and Plate VL, Fig. 23). 

 Considerable variations in size are met with in different cases 

 of dysentery; in some acute cases few am<eb;e may exceed 

 _M) fi in diameter. When at rest, a somewhat clear, highly 



/ <v, 



a b 



Fir;. 169. Amcebse of dysentery. 



<i and f>, amoebae as seen in the fresh stools, showing blunt amoeboid 

 processes of ectoplasm. The endoplasm of a shows a nucleus, three 

 red corpuscles, and numerous vacuoles ; that of 1>, numerous red 

 corpuscles and a few vacuoles. 



r, an amoeba as seen in a fixed film preparation, showing a small 

 rounded nucleus (Kmsc and 1'asquale). x600. 



refract! le ectoplasm and a granular endoplasm can be dis- 

 tinguished, a feature which differentiates the organism from 

 the entamoeba coli. The nucleus is rounded or oval, and 

 is seen with difficulty; its position is usually excentric, and is 

 sometimes quite at the margin of the ectoplasm. In the fresh 

 condition, and especially when examined on a warm stage, the 

 organism shows very active amoeboid movements. The pseudo- 

 podia, which are quickly protruded and retracted, are blunt 

 and apiiear to be of tough consistence, a property which 

 Sehaudinn considers of importance, as enabling the organism 

 to penetrate the mucous membrane, etc. The amoebic move- 

 ments are often of an active kind, and locomotion may be 



