Identified as M. Seymer's dog in the Silvy daybooks [the 'M' stands for 'Monsieur' and is used instead of 'Mr' throughout the first volume], the dog was identified as "Pilot" on the page of the album in which the carte was found. He was probably named after Mr Rochester's dog in Charlotte Brontë's Jane Eyre, published in 1847.

There is a portrait of the dog's owner on the precediing page of the daybook (Volume 1, page 4, sitting number 18), where he is identified as 'M. Ker Seymer'. Sitting number 19 is Mrs. Ker Seymer and sitting number 20 is Miss Ker Seymer.

The Mr Ker Seymer in question is almost certainly the politician Henry Ker Seymer (1807-1864), member of Parliament for Dorset.