Then I assume the motor to be a Genet or Genet Major and if this aeroplane postdates the Peto, my only other thought is a Blackburn Bluebird. However to postdate the Peto, it would have to be a Bluebird IV. But the fin and rudder doesn't look right for a Bluebird IV, and the only British registered floatplane version of this, of which I'm aware, was the Gipsy powered G-ABGF. The only Genet Major powered Bluebird IV, of which I'm aware, was a landplane and Australian registered, namely VH-UOC. The photograph looks much more like a Genet powered Bluebird II. The only floatplane version of this, of which I'm aware, was G-EBSW. But this aeroplane dates from 1927 (although it was not converted to a floatplane until 1930), whereas the two Petos apparently date from 1929/30, and in the photographs of G-EBSW which I've seen the engine mounting and cowling look subtly different from that in the photograph posted. All considered, Mike, I think that I've confused myself to the point of giving in and running up the white flag!