xiii, b, 5 Haughwout: Flagellated and Ciliated Protozoa 229 



nema, and have been asked to identify these new intestinal or 

 vesical parasites. Unfamiliarity with free-living species has 

 undoubtedly led to the discovery of "new protozoan parasites" 

 on some occasions. This should not, however, be construed 

 either as a reflection on the powers of observation of these 

 authors or a denial of the possibility that Trichomonas may be 

 capable of living in pond water. Like Balantidium, its food- 

 getting apparatus is adequate, and it is likely that it could secure 

 its proper food in sewage-polluted waters. But it remains to 

 demonstrate the fact experimentally one way or the other or by 

 the observation of the organisms in pond water. 



There was an outbreak of diarrhoea at Paranaque, a suburb 

 of Manila, in 1914. The local sanitary inspector at that place 

 assured me at the time that the diarrhoea was epidemic in the 

 town and that there had been a large number of cases, some 

 of which had been attended with fatal results. He stated his 

 belief that the trouble was due to Trichomonas, with which he 

 thought the sufferers had been infected through drinking river 

 water. He had no material at hand that I could study, and 

 pressure of other duties made it impossible for me to investigate 

 the matter further. 



Fantham, Stephens, and Theobald (13) believe that air, water, 

 and on some occasions food may be vectors of Trichomonas. 



As for Lamblia, Mathis(30) and Fantham and Porter (12) say 

 rats are transmitters and reservoirs for the species infesting 

 man. A similar condition may exist in the case of Trichomonas 

 and the other intestinal flagellates. It is pretty well established 

 that pigs are reservoirs and transmitters of Balantidium coli, 

 and the rat is under suspicion in connection with entamoebiasis. 



Unfortunately Hadley(20) does not figure the intracellular 

 stages of Trichomonas in his cases of blackhead in turkeys, and 

 we shall have to await his future communications for these. It 

 would be interesting to see how closely his intercellular parasites 

 coincide in appearance with Entamoeba histolytica as the latter 

 appear in sections through the intestine. Shorn of its flagella, 

 undulating membrane, and axostyle and possessing a nucleus 

 of the karyosome type characteristic of the entamoeba?, it is 

 not hard to see how Trichomonas could have been mistaken for 

 Entamoeba even by careful workers. 



Hadley speaks of the trophozoite stage in the lumen of the 

 intestine, as the period of youth during which the organism 

 divides by simple, longitudinal fission and accumulates a reserve 

 of food substance in the endoplasm. When this food reserve 

 has accumulated to a sufficient amount, this method of reproduc- 



