INTERNAL PARASITES 207 
23. Theobald. Parasitic diseases of poultry. London: Gurney & Jack- 
son, 1896. 
24, Walker. A short note on the occurrence of a leucocytozoén infec- 
tion. Host the ostrich. Union of So. Africa. Dep. Agr. Ann. Rpts. Dir. 
Vet. Res., 2, 1912, p. 384. 
25. Weinzirl. Trichomoniasis of chicks: a new and highly fatal dis- 
ease. J. Bact., Vol. 2, 1917, p. 441. 
26. Wickware. Intestinal parasites of poultry, their prevention and 
treatment. Dominion of Canada, Dep. of Agr. Health of Animals Branch. 
Bull. 25, 1917. 
27. Wickware. Is Leucocytozodn anatis the cause of a new disease in 
ducks? Dep. Agr. Canada. Rept. Vet. Dir. Gen., 1915, p. 95. 
28. Wilcox. The internal chicken mite. Montana Agr. Exp. Sta. Bull. 
22, p. 30. (Bibliography.) 
29. Williams. The air sac mite of the fowl. Am. Vet. Rev., Vol. 22, 
1898, p. 8. 
