Poliwag has a very thin skin. It is possible to see the Pokémon’s spiral innards right through the skin. Despite its thinness, however, the skin is also very flexible. Even sharp fangs bounce right off it. The direction of the spiral on the belly differs by area. It is more adept at swimming than walking. Its slick black skin is thin and damp. A part of its internal organs can be seen through the skin as a spiral pattern.
Pokédex entry #60
poliwag is a type water Pokémon that evolves first into poliwhirl and then into poliwrath.
poliwag in Pokémon GO
It's possible to hatch poliwag from an egg?
Yes, poliwag it's a Pokémon that can be hatched from an egg. poliwag can be hatched from a 5km egg.
How many CP would poliwag have after evolving?
If you’ve catched a poliwag and you want to know how many points it would have after evolving, use this evolution calculator and find out easily. You just need to write your Bulbasaur CP and then click “Evolve”.