marumaruko
Ghost Trainer
These prior-gen Pokemon are only those who have sprites in the demo.
So I can only deduce that these Pokemon are those only part of the Alolan Regional Dex.
[spoil]Caterpie
Metapod
Butterfree
Rattata
Raticate
Spearow
Fearow
Pikachu
Raichu
Sandshrew
Sandslash
Clefairy
Clefable
Vulpix
Ninetales
Jigglypuff
Wigglytuff
Zubat
Golbat
Paras
Parasect
Diglett
Dugtrio
Meowth
Persian
Psyduck
Golduck
Mankey
Primeape
Growlithe
Arcanine
Poliwag
Poliwhirl
Poliwrath
Abra
Kadabra
Alakazam
Machop
Machoke
Machamp
Tantacool
Tentacruel
Geodude
Graveler
Golem
Slowpoke
Slowbro
Magnemite
Magneton
Grimer
Muk
Shellder
Cloyster
Gastly
Haunter
Gengar
Drowzee
Hypno
Exeggcute
Exeggutor
Cubone
Marowak
Chansey
Kangaskhan
Goldeen
Seaking
Staryu
Starmie
Scyther
Electabuzz
Magmar
Pinsir
Tauros
Magikarp
Gyarados
Lapras
Ditto
Eevee
Vaporeon
Jolteon
Flareon
Porygon
Aerodactyl
Snorlax
Dratini
Dragonair
Dragonite
Ledyba
Ledian
Spinarak
Ariados
Crobat
Chinchou
Lanturn
Pichu
Cleffa
Igglybuff
Sudowoodo
Politoed
Espeon
Umbreon
Murkrow
Slowking
Misdreavus
Snubull
Granbull
Scizor
Sneasel
Corsola
Delibird
Skarmory
Porygon2
Smeargle
Elekid
Magby
Miltank
Blissey
Wingull
Pelipper
Surskit
Masquerain
Makuhita
Hariyama
Nosepass
Sableye
Carvanha
Sharpedo
Wailmer
Wailord
Torkoal
Spinda
Trapinch
Vibrava
Flygon
Barboach
Whiscash
Feebas
Milotic
Castform
Absol
Snorunt
Glalie
Relicanth
Luvdisc
Bagon
Shelgon
Salamence
Beldum
Metang
Metagross
Cranidos
Rampardos
Shieldon
Bastiodon
Shellos
Gastrodon
Drifloon
Drifblim
Mismagius
Honchkrow
Bonsly
Happiny
Gible
Gabite
Garchomp
Munchlax
Riolu
Lucario
Finneon
Lumineon
Weavile
Magnezone
Electivire
Magmortar
Leafeon
Glaceon
Porygon-Z
Probopass
Froslass
Lillipup
Herdier
Stoutland
Roggenrola
Boldore
Gigalith
Cottonee
Whimsicott
Petilil
Lilligant
Sandile
Krokorok
Krookodile
Tirtouga
Carracosta
Archen
Archeops
Trubbish
Garbodor
Vanillite
Vanillish
Vanniluxe
Emolga
Alomomola
Rufflet
Braviary
Vullaby
Mandibuzz
Fletchling
Fletchinder
Talonflame
Pancham
Pangoro
Sylveon
Carbink
Goomy
Sliggoo
Goodra
Klefki
Phantump
Trevenant
Zygarde[/spoil]
Total of 221 old Pokemon (including those with Alolan Forms)
OMG :/
No Aron line and no Bouffalant. I so wished they would be in this game, whether it's in-game or post-game.
As for the older Pokemon I get the feeling that's definite.