HISTOtOGY OF THE OVIDUCT OF THE DOMESTIC HEN. 4OI 



With this brief survey of the general anatomy of the oviduct 

 we may next turn to the details of its histology. In doing this 

 it will be advantageous to deal separately with the different 

 regions of the oviduct. 



Histology oe the Funnel Region. 



The extreme anterior portion of the oviduct is expanded into 

 a long slit like opening.' The walls of this opening are known 

 as the lips of the funnel. They are continuous with the mesen- 

 teries of the dorsal and ventral ligaments of the oviduct. From 

 these expanded lips the oviduct quickly converges to a com- 

 paratively narrow tube (fig. 453). This latter tubular por- 

 tion is known as the funnel neck. In the laying hen it varies 

 from 2 to 4 cms. in length.- The entire funnel portion is char- 

 acterized by its very thin walls and its very low longitudiftal 

 ridges. On the outer edge of the funnel li»ps the ridges are 

 only slightly raised. They gradually increase in height through- 

 out the length of the funnel. At the transition from funnel to 

 albumen portion they increase in height very rapidly. (Cf. fig. 

 453) The reason for this will be discussed in a later paragraph. 



Figure 457 shows under low magnification a transverse sec- 

 tion of the wall of the funnel lips. It is thus from the extreme 

 anterior part of the oviduct. To show the thinness of the walls 

 in this region as compared with other portions of the oviduct, 

 it is interesting to compare this figure with figures 462, 468 and 

 469. These figures are all reproduced with the same magnifi- 

 cation (i. e. X 30). From figure 457 we note the presence of 

 the very low longitudinal ridges. The epithelium is further 

 thrown into a number of secondary folds. The significance of 

 these folds will be discussed shortly. From this same figure we 

 may also note the presence of the outer layer of peritoneum 

 and immediately above this a more or less definite layer of 

 longitudinal muscles. Inside of this layer is the connective 

 tissue with scattered bundles of muscle fibers. In this region of 

 the oviduct the bundles of muscle fibers are scattered through 

 the connective tissue and are not sharply separated into definite 

 layers. Even here, however, the distinction between the outer 

 longitudinal and the inner circular layer is fairly clear and can 

 be traced in the figure. The inner layer at this point runs some- 



