EPITHELIOMA CONTAGIOSUM. 9 



For numerous cases of this disease for experi- 

 mental purposes I have to thank Mr. Cobb, the late 

 manager of the Manor Poultry Farm. 



B. Epithelioma Contagiosa:. 



A similar complaint to the preceding is found attack- 

 ing the comb and wattles of birds. This cutaneous 

 affection is known under a variety of names — more 

 generally, however, as Epithelioma Contagiosum and 

 Cutaneous Psorospermosis. 



Appearance of Disease. 



The disease, which is generally limited to the head, 

 manifests itself as vellowish-brown nodules varying 

 in size from a minute speck to a small bean. In 

 form the nodules are generally roundish, and become 

 at first depressed in the centre. On pressing them a 

 purulent yellow exudate appears. I have only seen 

 this disease on the head, but it has also been recorded 

 on the neck, rump, chest, and abdomen. It affects 

 Pigeons to a greater extent than Poultry. 



Prohahle Cause of Disease. 



After a time the nodules form crusts of a brownish 

 colour, and under these in the lowest parts I have 

 found numbers of Coccidia, which seemed to be 

 similar to those in diphtheritic growths. 



Rivolta regards these parasites as a distinct form 

 which he named Amoeba croapogena. So far as is 



