HISTOI^OGY OF THD OVIDUCT OF THE) DOMESTIC HE^N, 415 



crowded the ciliated cells to one side and have extended distally 

 beyond the former limit of the epithelium. This is the stage 

 immediately preceding secretion. In sections taken from an 

 oviduct at the point where a yolk was descending, the secretion 

 from these glands can often be seen pouring out in little streams 

 from, each cell. The nuclei of the gland cells are as a rule more 

 nearly circular in outline than the nuclei of the ciliated cells. 

 Further a very characteristic difference between the two kinds 

 of cells is found in the position of the nucleus. The nuclei of 

 the gland cells lie well towards the proximal ends of the cells, 

 while, as stated above, the ciliated cells have their nuclei towards 

 the distal ends. (Cf. fig. 465, 467, 470, and 471). 



One point should be mentioned in regard to technique in 

 studying these epithelial glands. While it is possible to demon- 

 strate the presence of these glands in the sections of every active 

 oviduct which I have examined, they do not show with the 

 same distinctness in all cases. When these g'lands are not filled 

 with secretion they are crowded back by the then larger ciliated 

 cells. In such cases casual examination of the epithelium shows 

 an almost completely ciliated surface. However the double row 

 of nudlei are present and more careful study of the section has 

 never failed to show the glands themselves. Further it is pos- 

 sible to demonstrate their presence by methods of differential 

 staining as given in a later paragraph. If, however, sections are 

 taken from a region where these glands are filled witti secretion, 

 they form the most conspicuous part of the epithelium. The 

 sections which show these glands best have been obtained from 

 oviducts in which the yolks had just passed the funnel region. 

 In such an oviduct the albumen region is just on the point of 

 extruding its secretion (cf. figs. 465 and 467). 



The question now arises as to whether the tubular glands, 

 which are derivatives of the epithelium, differ in the character 

 of their secretion from the goblet glands in the epithelium itself. 

 It is conceivable of course, that the two sets of glands are really 

 concerned in the secretion of the same substance, the only dif- 

 ference being that the invaginated portions have lost the ciliated 

 cells. On the other hand it is conceivable that the two sets of 

 glands secrete entirely different substances, and that a proper 

 mixture of the two are necessary to form the albumen as we 

 know it. 



