HISTOIvOGY Olf the; OVIDUCT OF THE DOMESTIC HE;n. 399 



haematoxylin, Kresylichtviolett, E'hrlich-Biondi, safranin and 

 gentian violet. Of these Heidenhain's haematoxylin v^as by 

 far the most useful. 



It is a pleasure to acknowledge my indebtedness to Miss 

 Maynie R. Curtis, assistant in this department, for attending 

 to the details of fixing, cutting and staining the sections used 

 in this work. 



General, Account oe the Structure oe the Oviduct. 



The oviduct of a hen consists of five more or less clearly 

 delimited regions. Beginning at the anterior end of the duct, 

 these are ordinarily designated as (i) the funnel, (2) the albu- 

 men secreting portion, (3) the isthmus, (4) the uterus or shell 

 gland and (5) the vagina.. The funnel, known in anatomical 

 terms as the ostium tubae abdominale, is a delicate thin walled 

 portion lying immediately ventral to the ovary. Its anterior end 

 is expanded into long lip like processes (fig. 453). The lips 

 quickly converge to form a rather narrow, thin walled tube. In 

 the functional oviduct the length of this tubular portion (fun- 

 nel neck) is from 2 to 4 cms. The epithelium on the wall of 

 the funnel is folded into rather low longitudinal spiral ridges. 



These ridges, with more or less interruption are continuous 

 throughout the oviduct (fig. 453). They are greatly increased 

 in height in the lower portions of the duct. Besides these 

 primary ridges the epithelium also forms smaller secondary 

 folds. These secondary folds are best developed in the poste- 

 rior portion of the funnel (cf. fig. 458). Their presence in 

 other portions of the oviduct is somewhat obscured by the 

 enormous development of the glands. As will be pointed out 

 farther on these secondary folds bear ■ important relations to 

 the large glands. 



The funnel region grades rather gradually into the albumen 

 secreting portion. Figure 453 shows the region where this 

 changes takes place. There is no difficulty in distinguishing 

 between the two regions. In the albumen portion the walls are 

 much thicker and the longitudinal ridges are very much higher 

 (fig. 454). This albumen portion is the longest of the five 

 divisions. Its average length is about 42 centimeters in the 

 functional oviduct. The division between the albumen portion 



