44 



Pigeon No. 29. The 14th of April, two drops of a young bouillon culture 

 of B. pyocyaneus were injected under the conjunctiva of the left upper eye-lid. 

 The next day the general condition was very much disturbed, the eye-lids 

 swollen and sticking together. The eye^lids contained much slimy secretion 

 and later two small croupous membranes had formed on the conjunctiva, the 

 conjunctivitis became putrid, and the secretion smelt offensively. Often, 

 pseudo-membranes appeared on the conjunctiva. A solid tumor formed in the 

 upper eye-lid. The cornea was turbid. Subsequently, the bird recovered. 



Pigeon No. 30. Was inoculated with i c.c. culture of B. pyocyaneus in 

 the peritoneal cavity. Six hours later, it was dead. 



Post-iMortem : The post-mortem examination showed an extended serous 

 putrid peritonitis. The spleen was enlarged and cultures from this organ pro- 

 duced a pure culture of the inoculated bacillus. 



From these ifew experiments with the B. pyocyaneus, it is apparent that 

 this bacillus can produce chicken diphtheria in its dififerent localizations in the 

 mouth, eyes, nose, lungs, etc. 



The virulence of the B. pyocyaneus is very soon lost by growing it in the 

 ordinary culture media, but the virulence can be increased by passing it through 

 several pigeons. 



Reviewing the results of our experiments with chickens and pigeons, and 

 comparing them with the symptoms of the natural disease, we conclude that 

 chicken-diphtheria or roup is a complex of putrid processes, especially affect- 

 ing the mucous membranes and the submucous tissues of the head. We could 

 produce aseptic putrid processess in chickens by inoculation of sterile turpen- 

 tine oil into the submucous tissue of the eye-lids, and always found the pus in 

 the form of a solid, cheesy mass, which showed no tendency to become soft 

 and liquid. Putrid processses in chickens seem to behave similar to those 

 often found in rabbits, that is, the pus appears as a dry, cheesy, solid mass, 

 not as a fluctuating abscess. (See the submucous and subcutaneous tumors 

 in chicken-diphtheria). 



In the cases of a severe putrid catarrh, the pus corpuscles often stick to- 

 gether, with the help of the abnormal secretion, from the mucous membranes 

 or glands (note the jelly-like masses in the eye-lids), and finally become large, 

 cheesy masses, which do not adhere to the diseased mucous membranes. 

 (Cheesy masses in the nose, eye-lids, pleura, and peritoneum). In the mouth 

 cavity, pharynx, larynx, and occasionally on the conjunctiva, the leucocytes, 

 which passed through the mucous membranes, may remain adherent to these. 

 Corresponding to the amount of transuded leucocytes and the degree in which 

 the mucous membranes have been destroyed by them, or by accompanying 

 fibrinous exudations, we observe pseudo-membranes of different severity and 

 size. 



The reason the transudated pus corpuscles remain attached to the surface of 

 the mucous membrane in the mouth, and often in the eyes, too, but not in 

 the nose, may be explained as follows: i. The leucocytes have a natural tend- 

 ency to stick together. 2. The described processes are very often accom- 

 panied by formation of pathological secretions (jelly-masses) in eyes and slimy 



