LIGAMENTS OF OVIDUCT OF DOMESTIC FOWL. 7 



of hatching. In other words, the dorsal Hgament maintains a 

 line of attachment to the body wall running from the caudal 

 end of the body cavity to the fourth thorasic rib. The free 

 ventral margin of the ventral ligament elongates very little dur- 

 ing the growth period, but becomes thick and muscular. The 

 distance between the attachment of the dorsal ligament to the 

 body wall and to the duct increases, varying somewhat in differ- 

 ent regions of the duct. The width of the ventral ligament 

 from its attachment to the oviduct to its free ventral margin 

 increases during growth except at its caudal end. Here the 

 ligament becomes simply a heavy mass of muscle. Thus at 

 sexual maturity the oviduct is suspended in a fold of perito- 

 neum which remains short at its dorsal and ventral margins 

 but which is elongated where it encloses the duct. 



The relation of the oviduct to the sheet of peritoneum which 

 forms the dorsal and ventral ligaments as well as the outer 

 covering of the duct itself was described many years ago by 

 Macartney in his article on "Birds" in Rees' Cyclopaedia, Vol. 

 IV. His description is as follows : "The ovarian tube or ovi- 

 duct during the season of laying, fills the greater part of the 

 lower belly; it forms a number of curves or convolutions simi- 

 lar to the intestines, which, hovrever, are not permitted the 

 same latitude of motion amongst each other, because the pro- 

 longation of peritoneum which includes the oviduct is remark- 

 ably strong, and is not so long as the parts it contains and there- 

 fore the convolutions are coiled close together and even some 

 of them are doubled up within the peritoneum. The dispro- 

 portion between the oviduct and the peritoneum, which invests 

 it, arises from the additional bulk the [oviduct] * acquires 

 when its functions are exercised whilst the peritoneum must 

 preserve at its back part its original extent, i. e.. the length of 

 the left kidney, from the middle of w^hich it is reflected." 



A? a result of the enlargement incident to commencing func- 

 tional activity the albumen secreting portion and the isthmus 

 are thrown into convolutions. The anterior and posterior elon- 

 gations of the funnel increase in length. The peritoneum cov- 

 ering the uterus elongates very little more than is necessitated 



* There is an obvious typographical error in the original text which 

 here reads "ovary" instead of "oviduct." 



