164 PROTOZOAN PARASITISM 



made out are the result of environment and medium 

 of growth. Should either or both of the other tri- 

 chomonads be shown to be identical with it the species 

 name wdll remain Trichomojias vaginalis. 



First seen by Donne in 1837, this parasite is a very 

 common inhabitant of the vagina, especially in the 

 presence of an acid leucorrhoea, although this state 

 may merely reveal it by calling for an examination. 

 It is usually found in the vault of the vagina in an 

 accumulation of greyish or white granular liquid 

 material, in which desquamated epithelium and vari- 

 able numbers of leucocytes are seen. Examined 

 fresh in this material the organism is usually larger 

 than either the intestinal or mouth trichomonad and 

 it is not as actively motile in its natural state. It is 

 seen crawling about in the debris and among the 

 desquamated cells, frequently elongating and extend- 

 ing a ''neck" which may be as long as the body is 

 ordinarily. It twists and turns upon itself and sel- 

 dom is of the active darting motion of Trichomonas 

 in a liquid stool. 



In material at the bottom of a culture tube it may 

 have the same appearances, frequently being clumped 

 in colonies, attached to solid materials. In liquid 

 medium it develops a rapid swimming movement like 

 the other trichomonads. 



Its variation in size is from 5 by 10 microns to 15 

 by 25 microns or even larger, the largest sizes being 

 in those preparing for or undergoing division. 



It has four anterior flagella, undulating membrane, 



