490 DIPHTHERIA IN FOWLS 
cases alone were examined the diphtheritic condition would not be 
suspected. It appears, however, that in the majority of cases the 
disease runs its course and membranes are formed, slough and recov- 
ery follows. It is furthermore presumable that the disease in question 
appears sometimes in a virulent and destructive form. Statements 
from poultry raisers show that there are occasionally epizodtics 
characterized by exudates in the eyes, nose or mouth, which terminate 
fatally. It appears that it is such outbreaks that have been reported 
in Europe as diphtheria and not the low form of chronic inflammation 
which has been studied in this country. 
3 r vi cl al 
a Fic. 116. , LONGITUDINAL 
SECTION THROUGH THE 
LARYNX AND TRACHEA OF A 
FOWL (SAME 4s 118), SHOW- 
ING THE EXUDATE: (a) IN 
THE LARYNX AND (b) INTHE 
TRACHEA. 
Fig.115.  DIPHTHERITIC EXU- 
DATE IN THE LARYNX OF A 
FOWL: (a) THE GRAYISH- 
WHITE EXUDATE PROJECTING 
FROM THE GLOTTIS. 
Diagnosis. Fowl diphtheria is to be diagnosed by the symptoms 
and lesions. There are no specific tests that are satisfactory. Itis to 
be differentiated from lesions of the head caused by injuries or other 
infections, and chicken pox. Manson’s eye worm (Oxyspirura 
Mansoni) of chickens produces lesions that might be mistaken for 
roup. The finding of this worm would determine the diagnosis. 
Relation of diphtheria in man to that in fowls. According to a few 
writers especially Nocard and Leclainche there are cases of diphtheritic 
