According to the book The Captive Luftwaffe - p. 91 - the canopy was
presumably (the word used in the book) removed to accomodate test
pilot Harvey Heyworth who was over 6 feet tall.

However, I would have though that it came into the possession of the
RAF after the original owner at first thought of bailing out but
changed his mind and decided to ditch instead. This explains how the
canopy was lost.

Who knows. The aircraft was used in the movie The Battle of Britain.
Today the aircraft is in Hendon museum. (At least as far as I can find
out. )

http://www.warbirdregistry.org/luftr...-wknr4101.html

Waldo.