228 



TROPICAL MEDICINE AND HYGIENE 



amoebae assume a spherical form, and are difficult to 

 distinguish from other mononuclear cells. Propagation 

 takes place by budding, division, or segmentation. Where 

 there is no diarrhoea the actively moving amoebae are not 

 found, as a rule, though they may be present in mucus 



Asexual multiplication by simple division of nucleus and cytoplasm. 



e ? l 



FIG. 65. Scheme of Development of Amoeba. Multiplication in encysted 

 forms (autogamous). ? sexual multiplication. The early stages of division 

 of the nucleus (ad) and conjugation of the divided nuclei in pairs (e), 

 followed by further division of these products of conjugation, first into two 

 and then into four each (fi). The thick wall of the cyst in the later 

 stages indicates the hardening of the cyst wall during the stages when the 

 cysts are outside the body. 



passed before, or after, or with a motion. Artificially 

 induced purgation, as by the use of saline aperients, will 

 usually result in the passage of active moving amoebae. 



Amoeba coli. This is a large amoeba, frequently '05 mm. 

 in diameter, though smaller forms are common. The 



