DISEASES OF POULTRY. 171 



cavities. Some authors stale that they have observed 

 them in yellow, miliary tubercles of the body cavities, 

 lungs, liver, and kidneys. Large numbers of the 

 Cytoditcs may exist in the air sacs without their pres- 

 ence being suspected during the life of the bird. 

 When thej' are very numerous in the l)ronchi they 

 cause irritation of the mucous membrane, catarrh and 

 coughing. Megnin states that they maj^ cause death 

 by congestion and obstruction of the bronchial tul)es. 

 Gerlach and Zundel believe that the Cytoditcs may 

 cause enteritis and peritonitis. In small numbers 

 these mites are not very injurious, but when birds are 

 badly infested thej^ become anaemic, lose flesh, stop 

 la3'ingeggs, show catarrhal S3miptoms, droop and die. 



The Harpirhynchus 7iidulans lives in tumors of the 

 skin on pigeons and sparrows. When present in small 

 numbers onl}' it is nearly harmless, and, at most, 

 causes slight local irritation and disturbance to the 

 growth of the feathers. If very numerous, there is 

 impaired nutrition, loss of flesh, and frequently a 

 fatal ending. 



The' Lamhiosioptes cysticola liv^es in the connective 

 tissue of the GaUinacece where it may cause irritation 

 and the formation of tubercles, in the center of which 

 are found the mites. They often exist without affect- 

 ing the health of the birds, but when in large numl^ers 

 there are the usual sj-mptoms produced by theepizoa, 

 /. c, bloodlessness, weakness, loss of flesh, and, 

 finall3^ death. 



The Falcigcr rostratus of the pigeon, which is really 

 one of the feather mites, is able to introduce itself 

 into the connective tissue beneath the skiu, which it 

 enters by way of the feather follicles, and there 

 spends a portion of its life. Rol)ertson examined a 



