INTERNAL PARASITES 193 
importance. J. columbe has been reported as causing the forma- 
tion of caseous foci in the liver of the pigeon with fatal result. 
Monas (Monocercomonas) anatis has been reported as occurring in 
the small intestine of the duck. Martin and Robertson have studied 
the flagellates of the ceca of fowls dividing them into the four 
species: Chilomastix gallinarum, Trichomonas gallinarum, T. 
eberthi and Trichomastix gallinarum. 
Hadley observes that the intestinal fauna of any young veieay 
after it has been on the ground for a few days will contain a variety 
of protozoan parasites. Among these, the most common are flagel- 
lates, certain sporozoa and amebas. At least three types of flagellates 
are usually present, Trichomonas, Chilomastiz and Lamblia. He 
considers that Trichomonas plays a pathogenic role in cecal and he- 
patic infection in birds comparable to intestinal and hepatic ame- 
biasis as observed in mammals. Hadley considers the flagellates de- 
scribed by him as identical with bodies described by Theobald Smith 
under the name Ameba meleagridis and the cause of blackhead in 
turkeys. He regards Trichomonas as a facultative parasite in that 
under certain conditions it exists as a harmless, ever-present intes- 
tinal parasite. According to this view the Z’richomonas under cer- 
tain unknown circumstances invades the tissues and causes disease. 
Trichomoniasis of chicks. Weinzirl has described a highly fa- 
tal disease of chicks attributed to a new species designated T'richo- 
monas pullorum. 
Symptoms. Chicks under a month old only are attacked. The 
disease most commonly appears about the tenth day after hatching. 
The affected birds droop, they huddle together, the wings drag, the 
eyes are closed and the skin of the head is pale. Acute cases suc- 
cumb in a day or two without showing diarrhea. Other cases be- 
come chronic, in which stage diarrhea is present. The temperature 
is subnormal and is usually about 102° F. The disease is not ob- 
served until late spring and summer. 
Morbid anatomy. Autopsy reveals no lesions except a gen- 
eral anemic condition. The ceca may be slightly enlarged and the 
contents thin and slimy. The parasites collect in the crypts of the 
mucosa frequently in pure culture. When diarrhea exists, the pro- 
tozoan may be found in the intestine and in the voided mucus. 
Etiology. The flagellate Trichomonas pullorum regarded by 
Weinzirl as the cause of the chick disease occurs in two forms. One, 
the pear shaped type moves about actively by means of flagella and 
also exhibits active ameboid movements. This type varies from 3.5 
