Here goes a list of missing pokemons. Some stopped appearing after unlocking generations (DAUG), so if you don't have it on your pokedex, catch em before further progress.
Paras (DAUG); Scyther;
Misdreavus; Magby (DAUG);
Ralts (DAUG); Vibrava;
I'll be adding more as I progress through the game. Feel free to add your missing pokemons.