16,1 Haughwout and Horrilleno: Intestinal Parasites 5 
v,oim, must have been contracted not later than the ninth month. 
This, also, was a light infection, although it was detected on 
the first concentration of the stool. Further reference will 
be made to this case later on. 
The protozoal and helminthal findings are recorded in Table 
1. In this table are considered only protozoa in the strict sense. 
“Blastocystis” and Spirochxta eurygyrata are excluded; but, in 
view of the recent work of Kofoid, Kornhauser, and Swezy(35) 
and of Brug(5) we include Wenyon’s “I Cysts” under the pro- 
tozoa without at this time expressing an opinion as to whether 
they are the cysts of Entamoeba nana {Endolimax nana) or “En- 
tamoeba williamsi.” 
So far as “Blastocystis” is concerned, we record it as a para- 
site without regard to its pathogenic or nonpathogenic possibil- 
ities. It was found alone, to the exclusion of all other parasites, 
in only one of our cases. In each case where we have recorded 
“Blastocystis,” we have done so only after satisfying ourselves, 
beyond a reasonable doubt, that we were not dealing with aber- 
rant cysts of some definitely known protozoon. We have class- 
ified all intestinal spirochsetes as Spirochasta eurygyrata for we 
were unable to determine, without a tedious and time-consum- 
ing series of measurements, whether or not we were encounter- 
ing any of the other spirochaetes that have been reported from 
the human intestine. 
Table 1 . — Protozoal and helminthal findings. 
Cases. 
Total 
infec- 
tions. 
With protozoa 
33 
41 
With protozoa alone . 
2 
With helminths 
138 
With helminths al*>ne . - 
49 
prntn7r*nl anH VtpImintBfll iivfAPtmTiQ 
31 
f^’pironhjp.fn. p.ii.Tjiayrn.fn. nlnne 
“Blastocystis” alone 
1 
The parasites recorded by us in this study lie in thirteen 
genera and as many species. We have adopted Brug’s designa- 
tion (5) of Entamoeba nana as Endolimax nana, and in the case 
of hookworm infections we have made no attempt to distribute 
them between the genera Ancylostoma and Neeator, but have 
simply recorded them as “hookworm.” 
The incidence of the various parasites is set forth in Table 2. 
Table 2 shows Trichuris trichiura to be the most prevalent 
