79th foot regiment uniform details?

[jf42]

https://en.wikipedia.org/wiki/Robert_Munro_Ferguson

Came across this portrait; his bio says he served in the 19th foot regiment, but I have never seen epaulettes in such a strange shape & form? Does anyone have any more examples or details about it?

Thanks

The shoulder decorations are the 'wings' that originally denoted the regiment's flank companies but which were authorised for all ranks c.1830 at which time flank company distinctions were abolished for Highland corps. Colonel Munro appears to be wearing pantaloons of the 79th's Cameron of Erracht sett, uniform for mounted duty as appropriate for the Commanding Officer and Adjutant.