l88 ANATOMY OF THE DOMESTIC FOWL 



ciliated columnar epithelium, and some goblet, or mucous cells. 

 The cells on the surface generally are long and slender; in the grooves 

 between the mucous folds the cells are shortest, reaching their 

 greatest length at the tops of the folds. 



The function of the vagina is the secretion, or formation, of the 

 outer shell cuticle commonly called the bloom, and also in certain 

 breeds, as indicated above, the tint. 



The cloaca furnishes a passage way from the vagina to the ex- 

 ternal world by way of the anus. The walls of the cloaca contain 

 glands. 



The Ligaments of the Oviduct. — It is held in position by two 

 Hgaments, one dorsal and one ventral. The dorsal ligament of the 

 oviduct is formed by a double layer of peritoneum with a very 

 small amount of connective tissue interposed. The peritoneiun is 

 also reflected over the oviduct. The ventral ligament of the ovi- 

 duct is narrower than the dorsal, but is similarly constructed. Both 

 hgaments are rather veil-like in appearance. During the first four 

 or five months of the growth of the yoimg female fowl the develop- 

 ment of the oviduct and its hgaments is in proportion to that of the 

 body. With the elongation that takes place about the time of func- 

 tionation, as described above, the hgaments enlarge in proportion 

 to the enlargements of the oviduct. The dorsal hgament maintains 

 a line of attachment to the body wall from the caudal end of the body 

 cavity to the fourth thoracic rib. The ventral hgament elongates 

 only shghtly during this developing period. It becomes thicker 

 and stronger and early develops a muscular coat. It also grows in 

 width except at the caudal end. At this point the hgament is 

 simply a mass of muscular tissue of the smooth or involuntary tj^e. 

 These hgaments are fan-shaped. 



The muscle fibers of the dorsal hgament of the laying hen, have 

 their origin in a line near the medial side of the dorsal margin. At 

 this point the bundles of fibers are quite thick, but are spread out 

 thinly toward the margin of the oviduct. Frequent anastomoses are 

 noted. The muscular fibers become continuous with the circular 

 ones of the oviduct. 



The ventral ligament of the oviduct of the laying hen is largely a 

 muscular cord 3 to 6 centimeters in diameter. The caudal end 

 is thicker, becoming gradually thinner toward the anterior portion. 

 The bundles of muscular fibers extend toward the oviduct blending 

 with the circular fibers of that viscus. The ligaments terminate 



