Bird Life. 



lOI 



In the diagram are shown a number of eggs of 

 different sizes in the ovary, a being one ready to 

 start upon its course to the outer world. 

 Sometimes in the ovary, sometimes 

 after it has entered the oviduct, the egg- 

 cell meets the sperm-cell, which has 

 travelled all this way to meet it. 



For this egg is not to suffer chance /? 

 of destruction, like the egg of the fish 

 that, rolled about by the waves, may 

 miss the indispensable union with the 

 sperm-cell. 



On the contrary, the bird employs the 

 method of the insect to solve this diffi- 

 culty, and the sperm is deposited by the 

 male within the duct of the female. 

 It is true the bird has no complica- 

 ted intromittent organ as has the in- 

 sect, yet there is sufficient modification 

 of structure at the outer end of the tube 

 through which the fertilizing fluid is to 

 pass to permit the desired result, and sperm and 

 egg-cell meet before the latter has entered the 

 world. 



In this asylum, safe from harm, the sperm-cell 

 seeks the egg-cell, often travelling as far as the 

 ovary itself to find it, when it enters and is com- 

 bined with it. 



The now fertilized egg-cell moves along the 

 oviduct, whose walls secrete for it a quantity of 



