16 FRIENDS WORTH KNOWING. 
the upper part 
lifting off like a 
lid. Lastly, the 
egos of the stout 
paludinee 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. 
erystals of lime, so that the infant within seems to wear a 
