Name: Silcoon and Cascoon
Classification: Cocon
Type: Insect
Number: 266 and 268
Evolution: Wurmple – Silcoon (level 7) or Cascoon (level 7) – Beautifly (level 10 from Silcoon) or Dustox (level 10 from Cascoon)
Length: 60/70 cm
Weight: 10/11 kilograms
Habitat: Deciduous forests
Description: Silcoon and Cascoon are the names for the cocoon in which Wurmple evolve into either Beautifly or Dustox respectively. Contrary to Caterpie and Weedle, when Wurmple enter the cocoon stage, they spin a cocoon which does not follow the shape of their transforming bodies, but is roughly spherical and nearly solid. They consume this cocoon during their transformation, creating room for their growing bodies. The ‘eyes’ in the cocoon are very thin layers of thread, where air and water can pass into the cocoon. Although both are necessary for the transforming Wurmple to stay alive, a lot of them drown after heavy rain. Especially Cascoon suffer from the rain, because they, unlike Silcoon, do not have the little ‘covers’ above the holes. Silcoon are generally found in trees, where they hang between the branches on strong threads. Cascoon, which are larger than Silcoon, usually lie on the ground, sometimes tied to trees, rocks or fallen branches in the same way Silcoon hang themselves in trees. Silcoon and Cascoon are not merely incapable of movement: it is of vital importance that they do not move. Moving a cocoon or placing it somewhere else will seriously disturb the development of the pokémon inside, making it weak upon emerging, or even killing it. Beautifly emerge three weeks after entering the cocoon-stage; Dustox take about a week longer to mature. The silk of the cocoons is used to make cloth. In most countries, it is now illegal to use the silk of cocoons with a pokémon in it and the cocoons can only be used once they have been discarded by the Beautifly or Dustox. However, the silk is much harder to unwind if the cocoon has been discarded and the longer the pokémon is in the cocoon, the more of the precious silk it eats. In fact, as the pokémon nears evolution, the cocoon often becomes semitransparent, so that you can see the Dustox or Beautifly within. Because of this, there are still a lot of illegal plantations where the pokémon are killed for the silk. The silk is very hard to colour and for a long time, only white (Silcoon) and lilac (Cascoon) silk was available. Thanks to modern science, Wurmple can now be genetically manipulated to produce threads of other colours. So far, scientists have had success producing orange and green silk.
In the picture, we see a cascoon (left) and silcoon (right). For size comparison with a human, we see a Cascoon on the ground and a Silcoon suspended in the air.

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