Dora, a young, irresponsible art student, marries Paul, who is thirteen years older, and finds him decisive, possessive, authoritative and violent: 'Something gentle and gay had gone out of her life'. She leaves him and 'passed the summer drinking and dancing and making love and spending Paul's allowance on multi-coloured skirts'. She then decides to return to him, and goes by train, very nervous. On the carriage floor she sees a butterfly crawling; picks it up and holds it safely until the train stops and she gets out and meets her husband who finds she has left his property on the train, and 'His face was harshly closed'. He asks her why she is holding her hands so oddly, and she opens them 'like a flower'; the butterfly 'flew away into the distance'.
Clearly this is a butterfly highly charged with symbolic value.