16,1 Haughwout and Horrilleno: Intestinal Parasites 5 
worm, 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 Spirochxia 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 Hntameba nana (Endolimax nana) or “En- 
tamceba 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 protozoén. We have class- 
ified all intestinal spirochetes as Spirocheta 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 spirochetes that have been reported from 
the human intestine. 
TABLE 1.—Protozoal and helminthal findings. 
Total 
Cases. infec- 
tions. 
WESUA DPORUNO A aks BACs; ace Gee oe ee he 33 41 
Ith Srl nine ck = ok eek cis ewe ere Seer ee OE CE ar 
Py eis NTO i ee oa aa cae haw. pe ah ae ae ome 80 138 
Ache Bee cy ictlie fe Ge cpg sae ete pte aia pula rte Metco hte Sete i wera ILI Bie See A S -  Rices ap ast 
Mixed protozoal and helminthal infections____._.._--..__-------------..----- OE} ccosteuss 
Spirotheia euvvourats sleme.c..xicics- 5c: 565 ss ade on ce SF Bcc ee. 
Petite” MNO a ee ae a 1d focccnecnc, 
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 Entameba nana as Endolimax nana, and in the case 
of hookworm infections we have made no attempt to distribute 
them between the genera Ancylostoma and Necator, 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 
