What clan!!!

[MacMillan of Rathdown]

Lincoln would be an extremely uncommon first name prior to 1865, and virtually unheard of as a first name among Scots at that time. Here's what we DON'T know:

1) we don't know where the photo was taken.
2) we don't know what "65" means.
3) we don't know who wrote on the back of the photo.

If we assume the photo was taken in New York in 1865 then we can also assume the man was born in 1825 since he looks about 40. He may or may not have been born in Scotland, but in either case it is highly unlikely that he would have been christened "Lincoln" as a first name.

Skauwt makes a good case for the "R" possibly being a "K", although I am not entirely convinced: I would expect "CH" instead of "K" to be used in spelling "Christie/Kristie", a fairly common Scottish name.

The first letter in the first word is the puzzler: "I", "G", "J", or "L" are all possibilities. And it is also possible that the first word is the name of the woman-- Linda-- and--Rustie, written by a cousin or sister, or some other family member, sometime after 1865...

In the end, it is all speculation.