29 



months old) with pathological secretions and exudation products. Several 

 times the eye-hds became swollen for a few days, but no typical roup disease 



could be produced. 



These results show that out ot lo healthy chickens, kept with diseased 

 ones, five became infected. In four cases, nasal catarrh appeared in from 6 

 days to i^4 months. In the same birds, pseudo-membranes sometimes ap- 

 peared in the mouth for a few days. In fowl No. lo only, they appeared 

 without any changes in the nostrils. Five fowl did not take the disease at 

 all, although they were exposed to the same infection. 



Of the 14 chickens and i pigeon (see later) which we attempted to infect 

 with secretions and exudations from diseased fowls, only two fowls (Nos. 4 

 and S) became diseased with roup. These experiments show that chicken 

 diphtheria, or roup, may be transferred. 



Experiments to Infect Healthy Fowls with Bacillus Cacosmus (the Roup 



Bacillus.) 



Fowl No. 3. Small hen, weak constitution, about one year old. 



Dec. 17.— The conjunctiva and the higher parts of the nasal mucosa were 

 irritated with dilute lactic acid, after which a portion of a young agar culture 

 of the roup germ (isolated from diseased hen 4) was rubbed in. 



Dec. 18.— General condition unchanged. At the right nostril, some fluid 



can be seen. 



Dec. 21.— At the right nostril, a small quantity 01 a slimy, putrid secretion 

 is apparent. Disagreeable smell. 



Jan. 8. 1902. — Typical chronic nasal catarrh is present. Mucosa of the 

 mouth is pale. Under the tongue, an irregular croupous membrane is lo- 

 cated, about I mm. thick. This membrane was difficult to remove, and after 

 removal the surface beneath bled. 



Jan. 9. — An extended new membrane has formed at the old place. It 

 -was again removed, and cultures were made from the mucous membrane ly- 

 ing beneath the false membrane, from which the roup germ was subsequently 

 isolated. 



Jan. 10 to Feb. 10. — Nasal catarrh remained chronic and putrid. The 

 croupous membrane disappeared after having reappeared after four daily 

 removals. Later, several small membranes appeared at different places in 

 the mouth. 



April 24. — The discharge from the nose has disappeared for 8 days, and 

 there is no disagreeable smell. All visible mucous membranes are extra- 

 ordinary' pale. General condition, norma!. No apparent loss o: flesh during 

 the disease. 



Fowl No. 13. Healthy hen, about 8 months old. 



Jan. 10. 1902. — 1/2 c.c. of a bouillon culture, made from parts of the epithel- 

 ial membrane under a removed croupous patch of diseased chicken 9, was 

 subcutaneously inoculated. The culture was not pure, but the most numer- 

 ous germ was the roup bacillus. .\t the place of inoculation, a hot tumor 

 appeared, and became slowly resorbed in a few days. 



