DISEASES OF POULTRY. 



73 



Fig. is.— Microscopic elements of thrush; n, a, and c, c, epithelial cells; 

 6, b, isolated spores of the Saccharomyces albicans; d, d, filaments of the 

 my celium ;- f, ^, /, k, terminal portions of the mycelium; h^ spores; r, ovoid 

 terminal cell. Magrnified 360 diameters. 



far as the proventriculus, a layer of thrush having the 

 same appearances to the naked eye and under the 

 microscope as were described by Eberth. 



Although, in the two recorded cases, the disease 

 existed in the lower part of the oesophagus, it is very 

 probable that it also occurs in the mouth of birds, a 

 location favorable for its development with most species 

 of animals. The disease does not appear to be very 

 common, although it might be quite frequent and still 

 not be recognized, as but comparatively few investi- 

 gators have given systematic attention to poultry dis - 

 eases. Thrush can be distinguished from other dis- 

 eases causing a similar deposit only by a microscopic 

 examination. The mycelium and spores of the fungus 



