l82 ANATOMY OF THE DOMESTIC FOWL 



per cent. There is apparently no constant proportion of weight 

 between the yolk and albumin. There is also a variation in the 

 weight of the shell due to its variation in thickness. 



In an examination of ten eggs of average size, the yolk constituted 

 31 per cent, of the total weight of the egg. 



The following is the result of the analysis of twelve eggs of average 

 size. This analysis included the shell and all other parts taken 

 together.* 



Moisture 64. 25 per cent. 



Dry matter 35-75 per cent. 



100.00 per cent. 



Parts per hundred including shell 



Protein 10. 2500 



Fat 10.6200 



Phosphorus 3020 



Calcium ■ 6080 



Magnesium 0985 



Iron 0103 



Sulphur 3950 



Chlorine 1506 



Potassium 0103 



Sodium : . . . , 2000 



The Oviduct. — The three separate and distinct portions of the_ 

 eggj albumin, shell membranes, and the shell, are constructed in 

 different parts of the oviduct. 



Location. — The oviduct of the hen extends along the left side of the 

 bodies of the vertebrae, and the roof of the pelvic cavity and hes 

 dorsal to the abdominal air-sac. It extends from the posterior 

 border of the ovary and empties into the cloaca (Fig. 56, No. 3 and 

 8) through a transverse sUt. 



Shape. — In a weU-developed Plymouth Rock pullet, but one 

 whose reproductive organs have never become active, the oviduct 

 is about 4^^ inches long; in the fully developed and active state it 

 is from 18 to 20 inches long, and in a collapsed state about 3^ inch 

 in diameter. It is held in position by two Ugaments, a dorsal and 

 a ventral (Fig. 55 5) to be described later. The oviduct is tortuous 

 in its course, forming three principle convolutions before reaching 



'The analysis was made by D. M. McCarty, chemist, Animal Industry 

 Division, North Carolina Experiment Station. 



