the Enfield Model 1853 saber bayonet has two "knobs" at the end of the hand guards, that turn down slightly. The French Model 1866 saber bayonet's hand guard loops down, into a semi-circle, on one side. No CW era saber bayonet had this feature.
For a picture of the Model 1866, click on the link below, and scroll down.
For a picture of the Enfield bayonet, go to http://22.214.171.124/search?q=cache:hDrk9hQPdTYC:www.relicman.com/weaba.htm+%22enfield+saber+bayonet%22&hl=en&ie=UTF-8.