Sunburn vs. suntan? Marrow bone?

I’ve read most of the James Bond books by Ian Flemming. In them, he wrote on more than one occasion that Bond was “working on his sunburn”; or M (or someone) would say, “Nice sunburn.” In the 1950s when these books were written, did “sunburn” in Britain mean “sun tan”?

Also: In one book M and Bond are at a club. M orders “marrow bone”. What is “marrow bone”? I have an image of a bovine femur split in half length-wise, exposing the marrow which M then ate with a fork. Is this some sort of delicacy? Is it still eaten?

Yes, I’ve heard of marrow being cooked especially. From this page:

I’d say, regarding the “sunburn” comments in Ian Fleming’s books, that they were a product of their time. In this interview, Roger More speaks about having skin cancer, and that:

Thanks, Ice Wolf. I wasn’t sure if “sunburn” was being used seriously or jokingly.