16 



FRIENDS WORTH KNOWING. 



the upper part 

 lifting off like a 

 lid. Lastly, the 

 eggs of the stout 

 paludinse of our 





THE APPLE-SNAIL, AND ITS EGGS. 



western lakes and rivers are not laid at all, but the embryos 

 hatch out in the oviduct. 



Under the microscope the translucent egg-envelopes pre- 

 sent a beautiful appearance, being studded with glistening 

 crystals of lime, so that the infant within seems to wear a 



