Type:Bug
Catch:All three versions.  Evolves from Metapod at level 10.
Here's the move list.

     Butterfree's flying abilities make it more
     versatile than some of the other Pokémon
     you'll find early in your adventure.

     TYPE: Bug/Flying
     HEIGHT: .6 m
     WEIGHT: 25 kg
     EVOLUTION: Caterpie-Metapod-Butterfree
Level        Attack        Type

12            CONFUSION    PSY
15            POISON POWDER    PSN
16            STUN SPORE        GRS
17            SLEEP POWDER    GRS
21            SUPERSONIC        NRM
26            WHIRLWIND        NRM
32            PSYBEAM          PSY