564 CERCOMONAS, TRICHOMONAS, HERPETOMONAS 



CERCOMONAS TRICHOMONAS HE RPE TOM ON AS. 



While trypanosomes are the most important flagellate from a 

 medical and veterinary standpoint, there are a few others which 

 are parasites of vertebrate animals, though most of them are not 

 pathogenic. 



Gercomonas. These are flagellates of a round or oval body, with 

 a pointed posterior end. The flagella are generally long. The 

 vesicular nucleus is situated near one or two contractile vacuoles. 

 Cercomonas hominis, first described by Davaine, 1854, has been 

 found in the human intestines, urine, and the sputum in disease (gan- 

 grene) of the lung. The organism is pear-shaped, with a pointed 

 posterior end, from 10 to 12 micra long; the flagellum is twice as 

 long as the main body. The nucleus is difficult to see. The organism 

 is most frequently found in the intestines of man in chronic diarrheas. 



FIG. 195 



FIG. 196 



Trichomonas vaginalis. (Blochmann.) 



Lamblia intestinalis. (Schewiakoff.) 



It is, however, not the cause of the pathologic condition, but only 

 finds in the fluid contents of the large intestines conditions favorable 

 to its parasitic existence. The following organisms of this family 

 have been found in domestic and other animals: Cercomonas anatis 

 (duck), Cercomonas canis (dog), Cercomonas gallinarum (chicken). 

 Several species of cercomonas have been found in the intestines of 

 guinea-pigs; two of them, Cercomonas pisiformis and Cercomonas 

 globulus, are believed to be pathogenic for this animal. 



Trichomonas. Trichomonas vaginalis. This organism is found in 

 the vaginal secretion and in the urine of females, occasionally also in 

 the urethra and urine of males. The organism is either pear-shaped 

 or circular. It varies much in size, and the measurements given are 

 from 10 to 25 micra; generally in length from 15 to 25 micra, and the 

 width from 7 to 12 micra. The protoplasm is finely granular and of 

 a greenish hue. The anterior end of the cell carries three, sometimes 

 four, flagella, which are about 10 micra long. 



Trichomonas Hominis, or Intestinalis. This is generally smaller 

 than the preceding one. It is a parasite of the ga.stro-intestinal 



