LIGAMENTS OE OVIDUCT OF DOMESTIC FOWL. 3 



opening" into the body cavity form the funnel (ostium tuhae 

 abdominalc or infundibulum) and the short tube forms the 

 cranial end of the tubular portion of the oviduct. The rest of 

 the oviduct arises by the caudal elongation of this short anterior 

 portion which grows backward between the tubal ridge and the 

 Wolffian duct to the cloaca. 



As development proceeds the duct enlarges and begins to 

 project from the ventral surface of the Wolffian body. The 

 peritoneum of the tubal ridge which covers the duct becomes 

 thin like the adjacent peritoneum. As development continues 

 the oviduct projects farther from the surface of the Wolffian 

 body which soon degenerates. The oviduct is finally suspended 

 by a ligament formed by a double sheet of peritoneum contin- 

 uous at the dorsal margin of the oviduct with the peritoneum 

 which surrounds the duct and reflected from the peritoneum 

 covering the dorsal body wall and permanent kidney along the 

 line of origin of the oviduct. At the end of incubation this 

 sheet of peritoneum which suspends and surrounds the oviduct 

 is continued a little below the ventral margin of the oviduct as 

 a narrow fold. The part of this sheet of peritoneum dorsal to 

 the duct may be designated as the dorsal ligament of the ovi- 

 duct (Fig. i) and the part ventral, as the ventral ligament of 

 the oviduct * (Fig. i). 



•^ 



J boJy_il3^ 



A 



Ostium : 

 P 



Fig. t. Diagram showing relations of tlie oviduct and its ligaments at 

 the time of hatching. .], anterior elongation of funnel; P, posterior 

 elongation of funnel. 



At the time of hatching the oviduct is still a straight thin 

 walled tube somewhat differentiated into the parts clearly dis- 

 tinguishable in the functional duct. These are (a) the funnel 



* This fold of peritoneum which forms the ventral ligament occupies 

 the position descrihed for the tubal ridge and it seems possible that this 



ridge may contribute to its formation. 



