Belemnotheutis reconstruction. (Yes that is the correct incorrect spelling if that made sense, has a story behind why it's spelled '-theutis' instead of the correct '-teuthis', but that's for another day, heh.
This is released under CC-BY and donated to Wikicommons.
EDIT:Updated pic after comments.
EDIT: Final revision.
EDIT:Not quite final. >.< Grrrrr... I was basing the fin shape on Gideon Mantell's description. Too old. Corrected fins.