376 University of Calif orni-a Publications in Zoology [Vol. 20 



MATERIAL 



In the course of 25,000 examinations of 7010 persons made by 

 us up to November 30, 1922, the latest date to which our statistics 

 have been assembled, we recognized 75 cases or 1.1 per cent infection 

 by Trichomonas hominis. The actual percentage of infection was 

 doubtless higher, since in the absence of cysts detection rests upon 

 finding living flagellates, and these in some types of stool do not 

 survive long and are usually infrequent in formed stools. In our 

 experience this species, except in dividing individuals, has only four 

 flagella. 



We found three cases in which there was an infection by Penta- 

 trichomonas ardin delteili (Derrieu and Raynaud). The first of these 

 was an army officer who had resided in the Philippine Islands and 

 Panama, and on and near the Mexican border. Nineteen examina- 

 tions of this case were made over a period of nine months. In each 

 case Pentairichomonas, and this flagellate only, was detected. 'There 

 was a concurrent infection by Strongylokles stercoralis and by Blasto- 

 cystis. The patient had a previous history of dysentry, had received 

 treatment for amoebiasis (emetin-bismuth-iodide and neoarsphena- 

 mine) and had gained in weight after this treatment. Chronic 

 diarrhoea marked the attack here treated. No free amoebae and no 

 amoebic cysts of any sort were found in any of the stools examined 

 by us, though diligently sought. 



The second case was also an armj' officer who had been stationed 

 for thirteen months on the Western Front in France, for a time in 

 an area where French African colonial troops and Chinese laborers 

 were billeted. To date seventy-eight examinations have been made 

 on this case. No worm infections have been found. There are con- 

 current infections by Chilomastix davainei and Blastocystis. Penta- 

 trichomonas was not found in only thirteen of these stools. In some 

 instances this was due to the condition of the stool resulting from 

 delay in shipment of the specimen from a distance. Chilomastix was 

 found in twenty-seven of the seventy-eight stools and was rarely 

 abundant. No other animal parasite was found in these examinations. 

 (Shortly before our examination began the patient had been found 

 to have amoebiasis and had received the emetin-bismuth-iodide and 

 arsphena^mine treatment.) No amoebae, free or encysted, were at 

 any time found by us in his stools. 



