These are a little rough around the edges, feel free to nit pick.
Spontaneous generation: Common species found on the earth today can be produced from inanimate chemicals, such as muddy puddles (frogs), meat left out in the sunlight (maggots and flies), or milk left in a jug for a long period of time (lactobacillus). No new species can be created from spontaneous generation, but instead the theory describes where they come from.
Abiogenesis: A self propagating chemical reaction starts that results in self replicating polymers. This gives rise to more complex chemical reactions due to accretion of small mistakes in the self replication reactions. Eventually, this results in cellular life due to capture in lipid bodies, followed by diversification into the species we see today.