Unhatched developing freshwater snail in its egg case. 100x magnification. Darkfield microscopy.

I end up with adult snails in the jars I collect pretty often and as long as there’s a decent amount of algal biomass in the jar, they can survive and feed and usually lay lots of egg clutches. These clutches are really cool to find because they’re transparent and gelatinous and you can see the developing baby snails on the inside of each egg moving around until ready to hatch.  

Many freshwater snail species are hermaphrodites, which means that an individual can have both sperm and eggs and reproduce without having sex with a partner. That’s why I can have a jar with just one adult snail and then in a few weeks, have dozens of snail babies moving around ready to have their pictures taken!