Diseases of the Reproductive Organs 261 



lium. These are called tubular glands. They consist of 

 long convoluted and branched tubules which open to the 

 lumen of the oviduct by short epithelial ducts. These 

 tubular glands are homologous, structurally at least, with 

 the glandular grooves of the funnel. The tubular glands 

 reach their greatest development in the albumen secreting 

 region. Histologically the unicellular epithelial glands 

 present a similar appearance in all parts of the oviduct ex- 

 cept the vagina. In this latter region the cells are longer 

 and much narrower and have a slightly different arrangement 

 than in other parts of the oviduct. 



The walls of the tubular glands consist of large gland cells 

 which in the albumen portion and the isthmus of a laying 

 hen have small, irregularly shaped, dark staining nuclei 

 which lie well towards the basal ends of the cells. In these 

 two regions the protoplasm of the cells contains rather 

 coarse granules which vary greatly in size. 



The line of demarcation between the albumen region and 

 the isthmus is characterized by the absence of these tubular 

 glands in that region. The cells of the tubular glands in 

 the albumen region and in the isthmus present the same 

 histological appearance. 



In the uterus the cells which form the tubular glands have 

 a somewhat different appearance. The nuclei of these cells 

 are large with regular outlines and are situated near the 

 center of the cells. The protoplasm is very finely granular 

 and is quite different from the coarsely granular condition 

 found in other parts of the oviduct. 



The tubular glands or any homologous structures are 

 entirely absent from the vagina. Only the unicellular 

 epithelial glands occur there. 



