This is a standard Constabulary socket which has had the spring used to retain it in the scabbard removed.  It is generally excepted that this was done when the sockets were issued to the Land Transport Corps during the Crimean War.

The blade is marked by the maker 'ROE' ^[1],  this is likely to be John Roe, noted as a Board of Ordnance supplier between 1835 and 1864.  It could also be G&E Roe noted in the 1850's,  although this maker normally marks the bayonets with 'G&E ROE'.