HISTOIvOGY OF THE OVIDUCT OF THE DOMESTIC HEN. 403 



ridges gradually increase in height from the almost flat con- 

 dition near the funnel mouth until they reach their greatest 

 development in the albumen secreting region. (Cf. fig. 462). 

 At the point of transition from funnel to albumen portion the 

 increase in the height of the ridges is more sudden. (Fig. 453). 

 The reason for this is seen if w^e compare figure 459 with 

 figures 457 and 458. Figure 459 represents under medium 

 magnification a section "of the inner layer of the oviduct wall 

 at the place where the funnel region passes into the albumen 

 portion. In figures 457 and 458 we note that the cores of the 

 longitudinal ridges are composed of connective tissue alone. In 

 figure 459, however, new structures appear in this connective 

 tissue core. These are sections of the tubular glands which 

 will be described later. From this point the tubular glands 

 increase rapidly in number arid size towards the posterior region 

 of the oviduct. Figure 459 shows only the inner layers of the 

 oviduct. The outer muscular and connective tissue layers here 

 do not differ materially from those shown in figure 458. 



We may now return to an exarhination of the epithelium in 

 the funnel region. Near the funnel mouth and over the upper 

 portion of the funnel neck the epithelium consists of only a 

 single layer of cells. These cells however, are of two distinct 

 kinds: (i) ciliated cells and (2) non-ciliated gland cells. As 

 shown in figures 457 and 458, the epithelium in this .region is 

 thrown into a large number of small secondary folds. Over the- 

 tops and sides of these folds there is a single layer of ciliated 

 cells. At the bottom of the grooves thus formed occur groups 

 of gland cells. Figure 460 shows one of these small glands 

 together with the character of the epithelium over the folds. 

 Figure 461 shows a larger and more typical gland from the 

 same region. Both figures are from the same oviduct. As 

 shown in the figures the ciliated cells are long and columnar in 

 shape. The slightly oval nucleus lies well toward the outer 

 distal end of the cell. , Each cell bears a number of large, strong 

 cilia. 



The non-ciliated .gland cells are shorter, and as shown in 

 figure 461 are usually more irregular in shape. These gland 

 cells in the active oviduct stain much deeper than the ciliated 

 cells. Especially is this true of the nuclei, many of which take 

 a very dark haematox3'lin stain. Figures 460 and 461 are both 



