156 University of California PiMications in Zoology [Vol. 20 



of the body is fairly symmetrical. Tricercomonas has a laterally dis- 

 placed caudal prolongation but no undulating membrane. Davaine's 

 Cercomonas hominis var. B, which has both characters, was therefore 

 the hiiman intestinal Trichomonas and its correct specific name is 

 hominis on the ground that Davaine had two species in his original 

 C. hominis and one of these, his var. A, was detached by Moquin- 

 Tandon (1860) as Cercomonas davadnei, leaving Davaine's var. B as 

 the residual species to retain the specific name hominis on the prin- 

 ciple of elimination. This name therefore replaces T. intestinalis 

 Leuckart (1879) and T. confusa Stiles (1902) proposed later as names 

 for the human intestinal Trichomonas. 



Teichomonas of the Human Mouth and Respiratory Tract 



There is much uncertainty as to whether or not there is more 

 than one species of Trichomonas in man. Species have been described 

 from the intestine {hominis, intestinalis), from the urogenital tract 

 {vaginalis), from the mouth {Tetratrichomonas buccalis, hominis), and 

 from the lungs {pulmonalis) . Two points of view and two possibilities 

 are open. (1) There is but one species in man which is modified by 

 the tissues and secretions which surround it, thus giving rise to the 

 morphological differences that have been detected among Trichomonas 

 from the different organs. This is the view of Jollos (1913). (2) There 

 are at least two species, the intestinal one and the one in the vagina. 

 There is also the possibility that there is a third species in the mouth 

 and that this may be the same as the one in the lung, though infection 

 in the lung by the intestinal form carried there in the blood stream, 

 or by invasion from hepatic abscess accompanying E ndamoeba dysen- 

 teriae, is also possible. Culture and inoculation of Trichomonas from 

 these different organs and much more morphological work accompany- 

 ing these experimental investigations will be necessary to determine 

 * the number of species. For the present it seems advisable to treat the 

 Trichomonas from the intestine {T. hominis (Davaine)), from the 

 vagina {T. vaginalis Donne), from the mouth {T. buccalis (Goodey 

 and WeUi7igs)) and questionably that from the lung {T. pulmonalis), 

 as separate species pending investigation. 



The recent work of Bensen (1909), Brumpt (191.3) and Lynch 

 (1915a, b) is indicative that there are morphological distinctions 

 between T. hominis and T. vaginalis, and the investigations of Goodey 

 and Wellings (1917) upon the flagellate of the mouth is suggestive 



