410 AGEICULTUEAL AND INDUSTEIAL BACTERIOLOGY 



which are motile by means of flagella ; 2. Rhizopoda includes 

 those motile by means of pseudopodia ; 3. Sporozoa includes 

 forms that are variously motile and greatly reduced 

 through parasitism. At some time in their life apparently 

 they all produce numerous spores. 



None of the group of Ciliophora, will be considered. 



One genus belonging to the Mastigophora, Trypanosoma, 

 includes organisms which are the cause of a variety of dis- 

 eases in man and animals. One genus belonging to Rhizo- 

 poda, Entammba, is the cause of amebic dysentery in man, 

 and three genera belonging to the Sporozoa, Babesia, Plas- 

 modium and Eimeria, cause Texas fever in cattle, malaria 

 in man and coccidiosis in fowls respectively. 



GENUS TRYPANOSOMA 



A trypanosome is a protozoan possessing an elongated 

 cell usually more or less spindle-shaped, occasionally almost 

 as broad as long but tapering at the ends. Practically all 

 of the forms which are of importance from the standpoint 

 of disease production are longer than broad when they are 

 observed in the blood. The posterior end of the cells ter- 

 minate in a flagellum, the length depending upon the 

 species. Along one side of the cell extending from one 

 end to the other is a thin membrane. The flagellum extends 

 along the membrane and forms its outer edge. The flagel- 

 lum finally enters the cells near the anterior end and 

 terminates in a granule (the blepharoplast ) which may 

 stain readily when treated with aniline dyes. 



The cells multiply by a splitting first of the blepharo- 

 plast, later followed by a division of the nucleus and a 

 longitudinal splitting of the cell. It is probable that some 

 at least, of the trypanosomes pass through a regular life 

 cycle. Some have been successfully cultivated in culture 

 media by mixing rabbit blood in melted agar and preparing 

 a slant in a test tube. The water of condensation is planted 



