  In this short notes we propose a new notion of contractibility for coloured
$\omega$-operad defined in the article published in Cahiers de Topologie et de
G{\'e}om{\'e}trie Diff{\'e}rentielle Cat{\'e}gorique (2011), volume 4. We
propose also an other way to build the monad for free contractible coloured
$\omega$-operads.
