There is no Richard E Buck to be found in the FReeBMD index of births.  Abroad?  Or another of those families that did not believe in registration?

However this household in the 1881 census almost certainly includes him and gives a birth of around 1856 (as his father was married, I wonder where his mother was):

Name Relation Marital Status Gender Age Birthplace Occupation Disability
Richard H.K. BUCK Head M Male 64 Bideford, Devon, England Clerk In Holy Orders Rector Of St Dominick
Richard E.S. BUCK Son U Male 25 St Dominick, Cornwall, England Clerk In Holy Orders Curate Of St Dominick
Ida F.H. BUCK Daur U Female 23 St Dominick, Cornwall, England
Eliza JENKINS Serv U Female 24 Perranzabuloe, Cornwall, England Cook Domestic Servant
Mary DAWE Serv U Female 22 Poole, Dorset, England Parlourmaid Domestic Servant
Jane PARKER Serv M Female 50 Lympstone, Devon, England Laundry Maid Domestic Servant
Jane MANUELL Serv U Female 17 St Breward, Cornwall, England Housemaid Domestic Servant
John HARRIS Serv U Male 29 Saltash, Cornwall, England Gardener Domestic Servant

Source Information:
Dwelling   Rectory
Census Place St Dominick, Cornwall, England
Family History Library Film   1341548
Public Records Office Reference   RG11
Piece / Folio   2283 / 65
Page Number   7
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Aug 2008, TFPL: The answer to the above conundrum is to be found in Burke's Peerage, 107th edition, vol III, p. 3801 for the Stucley (this does seem to be the definitive spelling) baronetcy.

The Bucks, for this was their original family name, inherited the Stucley estates at Affeton castle, Devon in 1755 from a Stucley cousin.  They kept the Buck surname until 1858 when George Stucley Buck changed his name to Stuckley by Royal Licence.  He became a baronet the following year, probably as a result of having been MP for Barnstaple from 1855 to 1859 (and again from 1865-8).  Sir George Stucley's (as he bacame) uncle was Capt Richard Buck RN of Bideford, Devon.

Richard Buck m. Angelica McDonald and they had, at least, a son Richard Hugh Keats Buck, rector of St Dominic, Cornwall, and a dau. Martha Buck who m. a Maj Oliver D'Arcy.

Burke give no more information of this Rev Richard Hugh Keats Buck but the above 1881 census entry is obviously about him and provides the explicit link to Richard Eustace Stucley (not Slukely as in the marriage certificate of his daughter!) Buck, the father of Constance A M Buck, wife of Stuart Trotter.

The forename of Keats came from Rev Richard's paternal grandmother.

I have changed his last forename from 'Slukely' to Stucley as the former has to have been a wrongly spelt in his daughter's marriage certificate.
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Vol 5c in the index is the same as the volume number for their daughter’s much later marriage, so I suspect this marriage was at Kenwyn church, Cornwall.

From the 1881 censuses, where both of the couple are clearly identified, he was 35 and she was 32 at marriage.
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