HISTOLOGY OF TK^ OVIDUCT 01^ THE DOMESTIC HlSN. 409 



Just as in the section from the middle of the funnel the so- 

 called cihated epithelium here also contains unicellular glands. 

 The arrangement of these is similar to that of those previously 

 described. In figure 464 the ciliated epithelium contains tv^^o 

 or more rows of nuclei. As before the outer smaller nuclei 

 belong to the ciliated cells. Between these latter occur the 

 gland cells with deeper, lying and usually larger nuclei. The 

 special histological description of these cells will be given in' 

 connection with the albumen portion, where they also occur. 



SUMMARY OF' SE;cTI0N ON HISTOLOGY OF THE^ FUNNEL. 



Six tissue layers are distinguished in the funnel walls. Two 

 of these are muscular layers, an outer longitudinal and an inner 

 circular layer. In the funnel region these layers consist for the 

 most part, of scattered bundles of fibers. On either side of the 

 inner layer of muscles is a layer of connective tissue. The 

 lumen of the funnel is lined with ciliated, glandular epithelium. 

 The outside of the oviduct is covered by a thin peritoneal layer. 



The inner surface of the oviduct is thrown into a large num- 

 ber of primary longitudinal ridges. The epithelium over these 

 ridges still further forms secondary folds. Three types of 

 glands are described. These are (i) the unicellular glands 

 occurring between the ciliated cells in the epitheliurn. These 

 g^lands are not found in the anterior half of the funnel. (2) 

 The glandular grooves. ThesQ are accumulations of gland cells 

 at the bottom of the grooves between the secondary folds of 

 the epithelium. These are found in all portions of the funnel 

 region except in the extreme posterior part. Here they are 

 replaced by (3) the tubular glands. These latter glands are 

 undoubtedly homologous with the glandular grooves found far- 

 ther forward. 



Histology of* the; Albumi:n Secrfting Rfgion. 



That part of the oviduct lying between the funnel and the 

 isthmus is ordinarily designated as the "albumen secreting por- 

 tion." While there is good reason to believe that the secretion 

 of albumen is not confined to this region alone, nevertheless it 

 is here that the major portion of this substance is formed. 



In the active oviduct of a Barred Plymouth Rock hen the 

 albumen portion measures, on the average, nearly 42 cm. in 

 length, or more than half the total length of the oviduct. 



