This Navy Lark

I spent a few hours last night going through pictures for the designer of Arrivals and Sailings: The Making of George Wyllie.
That's the name of the book which Louise Wyllie and I have written about her dad, the renowned Scottish artist George Wyllie.
George died in 2012 at the age of 90.
The word on the street is it's going to be published by Birlinn in April 2016.
Fear not, I'll be chuntering on about it at length nearer the time...
This shows George (or Ralston as he was known to all at this point) during his days in the Royal Navy.
He spent almost two years, from 1944-1946 on active service; the majority of it being in The Pacific.
Hence the tropical white uniform.
If anyone well versed in the ways of the Navy knows what one calls this uniform, I'd like to know. The caption has a couple of XXs marking the spot...

Picture courtesy The George Wyllie Foundation