190 DISEASES OF DOMESTICATED BIRDS 
soil was found necessary to secure penetration of the fluid to a depth 
of two inches. A trial of the effectiveness of the treatment in pre- 
venting the reinfection of birds that had been freed of worms yielded 
evidence of its value. Such birds increased in size rapidly and post 
mortem examination of the poorest specimens after three weeks 
yielded no evidence of worms. Other fowls on a control area, not 
disinfected, became seriously infested in a similar length of time. 
Bichloride treatment of roosting houses and other buildings to 
which birds have access, is indicated. Netting under the roosts is of 
value in keeping birds from contact with feces. 
Round worms in the pigeon. Heterakis columbe occurs in the 
intestines of pigeons in enormous numbers. As many as 400 to 500 
worms have been observed in one individual. The infestation causes 
loss of appetite, periodic mucous diarrhea and emaciation which is 
A B particularly marked in the pectoral muscles. At 
autopsy the worms are observed packed closely to- 
gether. The mucosa is distended in patches which 
are engorged with blood and ulcerated. These 
areas are covered with thick mucus. Occasionally 
the parasites perforate the wall of the intestine and 
are found in various parts of the thoracic and ab- 
dominal cavities. Treatment advised by Ziirn con- 
sists of administering 6 centigrams of calomel in 
- 29. Hetera- the form of pills with bread or with butter. More 
is columbe, A, _ . 
male; B, female. Serious cases may be treated with areca nut in 1 
Natural size. ovram doses, given in the same manner. Two hours 
(Railliet) a é a : : 7 
after administering the pills, each bird is given a 
teaspoonful of castor oil. The affected birds may be given a weak 
decoction of garlic to which one-half per cent of sodium salicylate 
has been added. 
Strongylus quadriradiatus has been observed by Stevenson in the 
intestine of the pigeon. The presence of a few worms causes no 
harm, but large numbers cause harm attributed to injury of the wall 
of the intestine permitting subsequent invasion by bacteria. 
TRICHOSOME INFESTATION OF CHICKENS 
Several worms of the genus T'richosoma have been described as 
harmless inhabitants of the intestines of fowls. However, Freese 
has observed that Trichosoma retusum is capable of causing great de- 
struction among chickens. The same parasite has been reported in 
the guinea-fowl. The worms vary from 13 to 19 mm. in length 
