01 - Bulbasaur
Grass
A strange seed is planted on Bulbasaur's back at birth which sprouts into a plant. The toad-esqe Bulbasaur makes up for lack of size with a will of iron–especially trained by someone like Ash. This Pokemon's confidence and ensnaring vine abilities make it a powerful ally. In "Bulbasaur and the Hidden Village - " Ash finds Bulbasaur to be very tough and extremely difficult to capture in the wild–but Ash finally captures it with great persistence.
Episode 10-"Bulbasaur and the Hidden Village"

02 - Ivysaur
Grass
Ivysaur is the second stage of evolution for Bulbasaur. When the bulb on its back grows large - Ivysaur appears to lose the ability to stand on its hind legs. In "Bulbasaur and the Hidden Village" Ash and company were treated to a wondrous surprise when they followed Bulbasaur to the Secret Garden of the Bulbasaurs-The time of evolution was upon them. Every year - the wild Bulbasaur migrate to a hidden location in the wild to evolve into Ivysaur. Ash's Bulbasaur was entranced - but then decided that it did not want to evolve yet.
Episode 51- "Bulbasaur's Secret Garden"

03 - Venusaur
Grass
Venusaur is the final stage in the evolution of Bulbasaur. The plant on Venusaur's back blooms when it is absorbing solar energy and it is constantly moving to seek sunlight. In "Island of the Giant Pokemon - " Ash and the gang wind up stranded on an island- but all of their Pokemon are missing. Pikachu - Squirtle - Bulbasaur - Charmander and the rest have their own adventure trying to get back to Ash - Misty and Brock. During their travels they run into a monstrous robotic Venusaur!
Episode 17- "Island of the Giant Pokemon"

04 - Charmander
Fire
This Pokemon obviously prefers hot places. When it rains - steam is said to spout from the tip of its flaming tail. According to the Pokedex - a Charmander dies if its flame goes out. Charmander's fiery personality is sure to brighten up a cloudy day. In "Charmander - The Stray Pokemon - " a Charmander is abandoned by an irresponsible trainer named Damion. Brock leads the group back into the forest to rescue it from a horrible rainstorm and attacking Spearows. Nurse Joy brings the resilient and eagerly excitable Pokemon back to health. Later - saving the group from an attack by Team Rocket - Charmander decides to abandon Damion and goes with his new friends.
Episode 11-"Charmander-The Stray Pokemon"

05 - Charmeleon
Fire
This is the second stage in the evolution of Charmander. When Charmeleon swings its burning tail - it raises the temperature around itself to unbearably high levels. In "Showdown at Dark City - " Ash's Charmander evolves into Charmeleon in an adventure in the decimated city known only as "Dark." Here our heroes get caught up randomly battling the local gym trainers throughout the town - destroying things wherever they go.
Episode 42- "Showdown at Dark City"

06 - Charizard
Fire
This is the final stage of evolution for Charmander. Charizard can spit fire that is hot enough to melt boulders - and is also known to cause forest fires unintentionally. In "Attack of the Prehistoric Pokemon - " Ash's Charmeleon evolves into Charizard so that it can pursue the once thought extinct Aerodactyl through the air.
Episode 46–"Attack of the Prehistoric Pokemon"

07 - Squirtle
Water
Squirtle can shoot powerful sprays of foam from its mouth. After birth - Squirtle's back swells and hardens into a shell. In "Here Comes the Squirtle Squad - " a group of unruly Squirtle briefly fall under the spell of Team Rocket and they capture Ash and his friends in an attempt to steal Ash's Pikachu. In a climactic battle - Team Rocket abandons The Squirtle Squad forcing Ash to rush to the aid of Squirtle.
Episode 12-"Here Comes the Squirtle Squad"

08 - Wartortle
Water
This is the second stage of evolution for Squirtle - and The Pokedex has very little information regarding this elusive water Pokemon. Wartortle often hides in the water to stalk unwary prey. For swimming very fast - it moves its ears to maintain balance and maneuver.
Ash has not yet encountered a Wartortle

09 - Blastoise
Water
Blastoise is the final stage of evolution for Squirtle. Blastoise can be a brutal Pokemon with pressurized water jets on its shell. These water jets are used for high speed tackles. Although an actual Blastoise has not yet appeared in the television series - a giant robot Blastoise shows up to cause trouble as our heroes and Team Rocket get marooned on an island of giant robotic creatures.
Episode 17- "Island of Giant Pokemon"

10 - Caterpie
Bug
Caterpie's short feet are all tipped with suction pads that enable it to tirelessly climb slopes and walls. In "Ash Catches a Pokemon - " the playful Caterpie dreams of a flowery future where it might fly free as graceful Butterfree. As Ash's first capture - this Pokemon saves the day from a surprise attack by Team Rocket by capturing the corrupt crew in its sinewy web and sending them off to oblivion.
Episode 3-"Ash Catches a Pokemon"

11 - Metapod
Bug
Metapod is the second stage of evolution for Caterpie. Metapod are vulnerable to attacks while their shells are soft - exposing a weak and tender body. In "Challenge of the Samurai - " Ash's Caterpie spins its first cocoon and evolves into the oddly shaped Metapod. The gang then encounters an ominous young samurai out to prove his worth as a Pokemon trainer. It's Metapod against Metapod as the two masters-to-be unleash their contestants to prove who is the greater Pokemon trainer. Metapod - Go!
Episode 4-"Challenge of the Samurai"

12 - Butterfree
Bug
Stage three of this Pokemon's evolution is the most gracious of all as the awkward shell of the Metapod bursts open and the brilliantly colored creature reveals itself to the world. In battle - Butterfree can flap its wings at high speeds to release highly toxic dust into the air. After Metapod sacrifices itself to save Ash from an attacking Beedrill in "Challenge of the Samurai - " the eager trainer's innocent Metapod is ripped open by the Beedrill's stinger and a Butterfree is revealed. A dream realized.
Episode 4-"Challenge of the Samurai"

13 - Weedle
Bug
Often found in forests - eating leaves - Weedle have sharp - venomous stingers on their heads. In "Challenge of the Samurai - " Dexter the Pokedex recalls encountering this shy bug Pokemon meeting up with Ash and Pikachu. As Ash traveled through the forest searching for new Pokemon - he encountered a timid Weedle. The Weedle - in a flurry of fright - climbed high up into the trees to escape.
Episode 4-"Challenge of the Samurai"

14 - Kakuna
Bug
Kakuna are the second stage of evolution for Weedle - and practically incapable of moving - this Pokemon can only harden its shell to protect itself from predators. While their powers are limited in this stage - Kakuna provided a clever camouflaged hiding place for Ash's Metapod after it was captured by a swarm of Beedrill.
Episode 4-"Challenge of the Samurai"

15 - Beedrill
Bug
This Pokemon is the final stage of evolution for Weedle. Beedrill fly at incredibly high speeds and they attack using the large venomous stingers on their forelegs and tails. The troublesome Beedrill are known for their quick attacks and violent tendencies. They traditionally gather in large swarms. A thorn in the side of all creatures - these mischievous Pokemon attack with fury and speed - usually without a moment's notice. In "Challenge of the Samurai - " a Beedrill entourage kidnaps Ash's Metapod and brings it back to their nest of sleeping Kakuna. Ash and company rescue Metapod - who then throws itself in front of Ash - to save him from a deadly Beedrill stinger attack.
Episode 4-"Challenge of the Samurai"

16 - Pidgey
Normal
Pidgey is the initial stage of evolution for this flying Pokemon. This Pokemon is a common sight in forests and woods and it can flap its wings at ground level to kick up blinding sands. Ash has in his Pokemon collection a Pidgeotto - the second evolutionary step of this bird Pokemon.
Episode 9-"School of Hard Knocks"

17 - Pidgeotto
Normal
This is the second stage of evolution for Pidgey. Very protective of its sprawling territorial area - this Pokemon will fiercely peck at any intruder. Pidgeotto is Ash's second capture. In "Ash Catches a Pokemon - " the hawk-like Pidgeotto loses its first battle with Team Rocket's Ekans and Koffing - even with the electrifying Pikachu at its side. A last ditch effort by Ash's new Caterpie saves the day.
Episode 3-"Ash Catches a Pokemon"

18 - Pidgeot
Normal
This is the final stage in the evolution of Pidgey. When hunting - this Pokemon skims the surface of the water at high speeds to pick off unwary prey such as Magicarp. Joe - a Pokemon Prep school student in "School of Hard Knocks" learns that when Pidgeot leaps into action it can fly at up to 1200 meters high at speeds of up to Mach 2.
Episode 9-"School of Hard Knocks"

19 - Rattata
Normal
Rattata is small and very quick - and is a common sight in many places. This pink-ish rodent creature will bite anything in its path. In "Bulbasaur and the Hidden Village - " Ash and Co. see two adorable Rattata frolicking about in the fields as our heroes enter the village. They then realize that the village is a great Pokemon sanctuary - where sick and abandoned Pokemon can recover and grow.
Episode 8-"Bulbasaur and the Hidden Village - "

20 - Raticate
Normal
This is the final stage of evolution for Rattata. It uses its long whiskers to maintain its balance - and it slows down if its whiskers are cut off. A terrifying Pokemon when trained properly - Raticate's fear inspiring look can surprise all but the most determined opponents. In "Battle Aboard the St. Anne - " Ash and company meets a distinguished gentleman and Ash trades his Butterfree for the gentleman's Raticate.
Episode 15-"Battle Aboard the St. Anne"

21 - Spearow
Normal
When wild and untamed - a flock of Spearow Pokemon can be a frightening and deadly thing. In Ash and Pikachu's very first outing they fend off the savage birds - saving one another's lives and as a result - form their unbreakable friendship. Spearow eat insects in grassy areas and have to flap their short wings at high speeds to stay airborne.
Episode 1-"Pokemon - I Choose You"

22 - Fearow
Normal
This is the final evolutionary stage for Spearow. The Pokedex has almost no information regarding this monstrous flying Pokemon - and the only data that was readily available was thisFearow - with its huge and magnificent wings - can keep aloft without ever having to land for rest.
Ash has not yet encountered a Fearow

23 - Ekans
Poison
Ekans is the deadly Pokemon owned by Jesse of Team Rocket - and she has trained it to attack its foes without mercy - squeezing the life out of its opponents. Ekans moves silently and stealthily and is known to eat the eggs of birds such as Pidgey and Spearow.
Episode 2-"Pokemon Emergency"

24 - Arbok
Poison
This is the final evolutionary step for Ekans - and it is rumored that the ferocious warning markings on Arbok's belly differ from region to region. Arbok is a deadly Pokemon in the wrong hands - and Jesse of Team Rocket definitely has the wrong hands. In "Dig Those Diglett - " Jesse's Ekans finally evolves into the powerful Arbok - bringing tears of joy to the nasty villain's eyes.
Episode 31 -"Dig Those Diglett"

25 - Pikachu
Electric
I choose you Pikachu! As Ash's first Pokemon - Pikachu makes a shocking impression on the Pokemon master-to-be. This lovable and cuddly Pokemon may look innocent - but threaten its owner and you'll get a jolt of 10 - 000 volts of thunder shock protection. When several of these Pokemon gather together - their electricity can build and cause lightning storms.
Episode 1-"Pokemon - I Choose You"

26 - Raichu
Electric
Raichu is the final evolved form of Pikachu. Raichu's long tail serves to ground it - thereby protecting itself from its own high voltage power. In "Electric Shock Showdown! - " the heroes finally arrive at Vermillion City - and discover dozens of Pokemon being treated for injuries received while battling the local gym leader Lt. Surge. Despite overwhelming odds - Ash challenges Lt. Surge and pits his Pikachu against a surprise opponent–Lt. Surge's fiercely trained and quickly evolved Raichu. Pikachu - despite its small size - defeats Lt. Surge's Raichu in the end!
Episode 14-"Electric Shock Showdown"

27 - Sandshrew
Ground
Sandshrew burrows deep underground in arid locations far from water - and will only emerge to hunt for food. Sandshrew is an innovative Pokemon when coached by the right trainer - like A.J.–a gym leader with unique and strenuous training methods. Sandshrew can dive and roll itself up into a ball then hurl itself at ground or airborne attackers. A.J.'s Sandshrew can withstand water due to its training with a custom built strength training harness. In "The Path to the Pokemon League - " Sandshrew shows its power by splitting open the earth as it wins A.J.'s 100th battle against Team Rocket's Ekans and Koffing.
Episode 8-"The Path to the Pokemon League"

28 - Sandslash
Ground
This is the final stage in the evolution of Sandshrew. The Pokedex has almost no information regarding this ground Pokemon - and the only known facts about Sandslash are as followsSandslash curls up into a spiny ball when it feels threatened - and it can roll while curled up to attack or to escape.
Ash has not yet encountered a Sandslash

29 - Nidoran
Poison
Dexter - the Pokedex - is knowledgeable about almost all of the Pokemon in the world - but there are some that still have yet to be categorized. Nidoran - and the entire species of Nidoran - have very limited information available. The Pokedex has this to say about the female NidoranAlthough small - the Nidoran's venomous barbs render this Pokemon dangerous. The female of this species has smaller horns than the male.
Ash has not yet encountered a Nidoran

30 - Nidorina
Poison
As with the Nidoran's first evolutionary step - the Nidoran - there is very limited knowledge available for the Nidorina. Dexter has this information in The PokedexThe female Nidoran's horns develop slowly. These Pokemon prefer physical attacks such as clawing and biting. This is the second stage of the evolution of the female Nidoran.
Ash has not yet encountered a Nidorina

31 - Nidoqueen
Poison
The Pokedex is a wealth of Pokemon knowledge and it has this to say of NidoqueenIts hard scales provide strong protection - and its ponderous body is surprisingly agile. Nidoqueen uses its hefty bulk to execute powerful moves. This is the final evolutionary step for the female Nidoran.
Ash has not yet encountered a Nidoqueen

32 - Nidoran
Poison
As with the female half of the Nidoran species - the Pokedex has very limited knowledge on the male half of this poison Pokemon species. Dexter has this to say of the male NidoranIt will stiffen its ears to sense danger around it - and the larger the male's horns - the more powerful its secreted venom.
Ash has not yet encountered a Nidoran

33 - Nidorino
Poison
This is the second stage of evolution for the male Nidoran. Nidorano is an aggressive Pokemon that is quick to attack - and the horn on its head secretes a very powerful venom. If the Pokemon League could find a Nidorino in the wild to study - numerous questions would be answered - like - "Do the Nidorino's spikes shed when it evolves - or does the Nidorino's poison work on other Nidorino?" These are questions we may never know the answer to.
Ash has not yet encountered a Nidorino

34 - Nidoking
Poison
This is the final - and most powerful evolutionary stage for the male Nidoran - and this creature is truly the king of all that it surveys. Nidoking uses its powerful tail in battle to smash - constrict and then break the bones of whatever had attacked it. The Pokedex has very little information on this powerful Pokemon and the rest of its remarkable species. Perhaps one day a Pokemon master will capture one of them to study-
Ash has not yet encountered a Nidoking

35 - Clefairy
Normal
In "Clefairy and the Moon Stone - " our heroes discover many injured Pokemon while taking a short cut to Cerulean City through Mt. Moon. They search for the mysterious Moon Stone reported to possess the capability of "powering up" weakened Pokemon. In a battle with the always interfering Team Rocket they are helped by a group of Clefairy - an extremely rare Pokemon. They're very magical and their utterly cute appeal has many admirers.
Episode 6-"Clefairy and the Moon Stone"

36 - Clefable
Normal
This is the evolved form of a Clefairy. Clefable are timid fairy Pokemon that are rarely seen. They will run and hide the moment they sense any humans. In "Clefairy and the Moon Stone - " Ash and friends all bear witness to the wondrous magic of the stone on the enchanted Clefable Pokemon.
Episode 6-"Clefairy and the Moon Stone"

37 - Vulpix
Fire
In "Pokemon Fashion Flash - " Brock convinces his friends to stop by Caesar Street and go into a Pokemon salon run by the beautiful Coron. In Coron's salon Brock is introduced to Vulpix-a beautiful and gracious Pokemon that - at the time of birth - has just one small tail. The tail then splits from its tip as the creature grows older.
Episode 28-"Pokemon Fashion Flash"

38 - Ninetails
Fire
This Pokemon is the final evolved form of a Vulpix. Ninetails is very smart and very vengeful - grabbing one of its many tails could result in a 1 - 000-year curse. The Pokedex has almost no information on this fire Pokemon. As with many Pokemon - Ninetails can't be found in the wild at all - to obtain one - one must nurture a Vulpix until it evolves.
Ash has not yet encountered a Ninetails

39 - Jigglypuff
Normal
When Jigglypuff's huge eyes light up - its beautiful siren song will soothe the savage beast - if you can stay awake long enough to hear its melodious and calming offerings. The tempermental creature gets frustrated - however - because its audience can never stay awake for an entire song. Jigglypuff has been known to draw vandalistic graffiti on the faces of its sleeping audience in frustration.
Episode 45–"The Song of Jigglypuff!"

40 - Wigglytuff
Normal
This is the evolved form of a Jigglypuff. There is practically no information regarding this evolved Jigglypuff in the Pokedex database. This is all the data that is availableThe body of this Pokemon is soft and rubbery and when Wigglytuff is angered - it will suck in air and inflate itself to an enormous size.
Ash has not yet encountered a Wigglytuff

41 - Zubat
Poison
Zubats are bat-like creatures that usually form colonies in perpetually dark places and do not like to be bothered. They also use ultrasonic waves to identify and approach targets of attack. In "Clefairy and the Moon Stone - " while searching for a short cut to Cerulean City through the dark and eerie caves of Mt. Moon - our band of heroes rescue a researcher named Seymour who is being attacked by a vast number of Zubat.
Episode 6-"Clefairy and the Moon Stone"

42 - Golbat
Poison
Golbat is the final evolved form of a Zubat. The evolved Golbat is a very powerful Pokemon - for once Golbat strikes - it will not stop draining energy from the victim even if it gets too heavy to fly away.
Ash has not yet encountered a Golbat

43 - Oddish
Grass
According to the Pokedex - Oddish is typically found roaming the forest at night - scattering pollen as it walks around. During the daylight hours - it keeps its face buried in the ground. In "Bulbasaur and the Hidden Village - " Ash and Misty argue over who will catch the leafy topped Pokemon while Bulbasaur thwarts their attempt by rescuing Oddish.
Episode 10-"Bulbasaur and the Hidden Village"

44 - Gloom
Grass
Gloom is the second evolutionary stage for Oddish. The fluid that oozes from Gloom's mouth is not drool - it is a sweet nectar that is used to attract prey. In "Pokemon Scent-sation - " we see how the gym leaders of the famed Celadon City Gym train and battle Pokemon - and we also see how they use the spores from Gloom to create their wonderful perfumes.
Episode 26-"Pokemon Scent-sation"

45 - Vileplume
Poison
Vileplume is the final evolutionary stage for Oddish. The larger its petals - the more toxic pollen it contains. Vileplume's big head is heavy and hard to hold up - causing a tremendous balance difficulty for this Pokemon. In "Pokemon Scent-sation - " Ash and Co. have their hands and noses full as the Celadon City Gym/Perfumery goes up in smoke at the hands of the nefarious Team Rocket.
Episode 26-"Pokemon Scent-sation"

46 - Paras
Bug
Paras burrows into the Earth to suck on tree roots. In "The Problem with Paras - " a beautiful girl with a knack for healing Pokemon saves the ailing Meowth. In a debt of gratitude - Team Rocket helps her evolve her Paras into Parasect.
Episode 44-"The Problem with Paras"

47 - Parasect
Bug
Parasect is a host-parasite pair in which the parasite mushroom has taken over the bug host. This Pokemon prefers damp places - and is the evolved form of Paras. In "The Problem with Paras - " Team Rocket instills Paras with self-respect and it evolves into Parasect. Meowth - Jesse and James all take credit for this feat but they also have other plans for this bug Pokemon-
Episode 44-"The Problem with Paras"

48 - Venonat
Bug
Venonat is a furball-shaped - fanged Pokemon. It lives in the shadows of tall trees and loves to eats insects - and is attracted by bright lights at night. In "The Ninja Poke-Showdown - " Ash and the gang are attacked by a female ninja and her trained Venonat. The battle rages until her brother - the master ninja - arrives on the scene to finish the battle.
Episode 32-"The Ninja Poke-Showdown"

49 - Venomoth
Bug
Venomoth is the final evolved state of Venonat. The dust-like scales covering Venomoth's wings are color-coded to indicate the type of poison that it is carrying. In "The Ninja Poke-Showdown - " the ninja master of Fuchsia Gym uses his Venomoth to combat Ash. The battle rages onward until Team Rocket makes their entrance. Ash and the ninja combine forces to repel the bungling bad guys - and Ash earns his next badge!
Episode 32-"The Ninja Poke-Showdown"

50 - Diglett
Ground
This mole Pokemon lives about one yard underground where it feeds on plant roots. It sometimes appears above ground-but only rarely. In "Dig Those Diglett - " Ash and friends discover a construction site where the foreman is asking Pokemon trainers to get rid of the pesky Diglett interfering with his work.
Episode 31-"Dig Those Diglett"

51 - Dugtrio
Ground
Dugtrio is the final evolved form of Diglett. This tunneling terror is a Pokemon team of Diglett triplets. It triggers huge earthquakes by burrowing 60 miles underground. In "Dig Those Diglett - " Ash and Pikachu are able to defeat the burrowing fury of these enraged Pokemon.
Episode 31-"Dig Those Diglett"