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MORPHOLOGY AND CULTURE OF MICROORGANISMS 



organisms which have been found, occasionally in the human intestine 

 and vagina, and in necrotic material from the lungs. Trichomonas 

 is a pear-shaped organism which has four flagella attached to its blunt 

 end, and an undulating membrane extending from the origin of the 

 flagella at the anterior end posteriorly over the surface of its body. 



FIG. 97. Trichomonas eberthi, from the intestine of the common fowl; ///., 

 anterior flagella, three in number; P.fl., posterior flagellum, forming the edge of the 

 undulating membrane; chr. I., "chromatinic line," forming the base of the undulating 

 membrane; chr.b., "chromatinic blocks;" bl., blepharoplast from which all four 

 flagella arise; m., mouth opening; N., nucleus; ax., axostyle. (From Minchin, after 

 Martin and Robertson.) 



One of the four flagella is usually directed backwards and extends along 

 the border of the undulating membrane. One species is sometimes 

 found in the human bladder. Other species are common, usually 

 harmless, parasites in the intestines of pigs, frogs and other animals. 

 The most important species of the genus Lamblia is Lamblia intestinalis. 

 It also is a pear-shaped organism. It has several flagella and is dis- 

 tinguished by possessing a depressed sucker, by which it attaches itself 



