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meet and coalesce. The food is thus enclosed and engulfed ; 

 and in this way a food vacuole is formed. It may contain 

 a little water ; but most of the liquid is a digestive ferment 

 secreted by the surrounding protoplasm. The ferment 

 has a solvent action on proteid matter, but not on starches 

 and fats. Ultimately, when nothing remains but a residue 

 of waste, the food vacuole is moved to the surface where 

 it bursts and discharges. 



How does the Amoeba breathe ? 



It takes in oxygen and gives off carbon dioxide all over 

 the body. 



Describe its Method of Reproduction. 



The normal mode of reproduction, when the limit of 

 growth has been attained, is by division into two daughter 

 individuals (simple fission). Fission is preceded by division 

 of the nucleus. Amoeba proteus sometimes encysts, a 

 process involving complex changes and divisions of the 

 nucleus followed by division of the cytoplasm, and resulting 

 in the formation of numerous small amoebae. 



OTHER EXAMPLES OF THE CLASS LOBOSA. 



Indicate the Importance of Entamo&ba coli and Entamozba 

 histolytica. Where are they found ? 



They are internal parasites of Man. Entamoeba coli is 

 lound in the upper portion of the large intestine. It occurs 

 in normal and healthy individuals, and is not (so far as 

 is known) associated with any particular form of disease. 



Entamosba histolytica is the cause of certain forms of 

 tropical dysentery. It occurs in the mucous membrane 

 of the intestine, and in the liver where it produces abscesses. 



Briefly describe ARCELLA and DIFFLUGIA, and show how 



they differ from Amoeba. 



ARCELLA is found in moor pools amongst wet moss 

 (especially Sphagnum). It is an amoeboid form with a 



