tl4 INTESTINAL FLAGELLATES OF MAN 



C. Polyzoic Forms. 

 5. Order: POLYMONADIDA. 

 The flagellates included in this order are polyzoic, and possess many 

 nuclei and blepharoplasts, each of which gives origin to one or more 

 flagella. In association with each nucleus, there may be a parabasal, 

 while an axostyle is present. The members of this order may be sup- 

 posed to have been derived from flagellates of the Eutrichomastix type, in 

 which multiplication of nuclei and organs has taken place without division 

 of the body. The order includes the single family CalofiymphidcB, founded 

 by Grassi for certain flagellates of termites which have the above charac- 

 teristics. The family includes several genera, such as Calonympha (Fig. 

 301) and Stephanony mpha (Fig. 302). 



FREQUENCY OF INTESTINAL FLAGELLATE INFECTIONS OF MAN. 

 Human beings are commonly liable to infection with the following 

 five intestinal flagellates : Giardia intestinalis, Chilomastix mesnili, Tricho- 

 monas hominis, Embadomonas intestinalis, Tricercotnonas intestinahs 

 (Fig. 303). The flagellated organism described by Kofoid and Swezy as 

 a species of Craigia, but which is probably a species of Sphceromonas or 

 Oikomonas, possibly identical with S. conmiunis, described by Liebetanz 

 (1910) from the rumen of cattle, is undoubtedly of rare occurrence. The 

 last-named organism has been seen only by Kofoid and Swezy in five 

 persons resident in America, and in one person who had returned from 

 India (see p. 295). Tricercomonas intestinalis was seen in about a dozen 

 cases of diarrhoea by the writer and O'Connor (1917) in Egypt. It is a 

 small flagellate which is exceedingly difficult to identify. It was seen by 

 the writer again in several cases of diarrhoea in Macedonia in 1918. Kofoid, 

 Kornhauser, and Plate (1919) record three cases of infection in soldiers 

 returned to America from abroad. The possibility of the identity of this 

 flagellate with the form described as Enteromonas hominis has been dis- 

 cussed above (p. 653). It is probable that it is of fairly common occur- 

 rence, as recent observations have extended its known distribution. 

 The difficulty of identifying it accurately may lead to its being regarded as 

 a small form of Trichomonas ho?ninis, Chilomastix mesnili, or even Emba- 

 domonas intestinalis. The last-named flagellate was seen by the writer 

 and O'Connor (1917) in two cases in Egypt. It was again recorded by 

 Kofoid, Kornhauser, and Plate (1919) in four patients returned to New 

 York from overseas, and in four others who had never left the United 

 States. A case was also seen by Hogue (19216) in the same country, while 

 another was seen by Broughton-Alcock and Thomson, J. G. (1922a), in a 

 person who had returned to England from abroad. It has since been 

 recorded from other localities. 



