Whatever happened to Cyril Ring?

A film trivia question. What actor appears alongside The Marx Brothers, W.C. Fields, Laurel & Hardy and Abbott & Costello, as well as featuring in all of the following films:
The Strange Love of Martha Ivers, Laura, Mr Skeffington, The Seventh Victim, I Married a Witch, Holiday Inn, This Gun For Hire, Saboteur, Sullivan's Travels, Two-Faced Woman, Meet John Doe, The Lady Eve, North West Mounted Police, The Great Dictator, The Roaring Twenties and a little something called Citizen Kane?

The answer is Cyril Ring. Poor Cyril Ring.

It seems to me he makes a perfectly good job of villainous Harvey Yates in The Cocoanuts. But for some reason he got the most terrible reviews, and his career didn't so much decline as nosedive almost immediately afterwards.

Okay; many stars don't make it, perhaps the majority of Hollywood careers are brief. Stars are rare, numerically speaking at least. But the sad thing about Cyril Ring is that he didn't disappear. He kept working in the movies until the early fifties, making many, many films a year throughout that time, for virtually all the major (and minor) studios.
But always in the tiniest roles, demeaning walk-ons, a glorified extra, perhaps a line or two at most, always there, somewhere; turning up for the cheque, doing next to nothing. A face in the crowd, but a haunting one. Once you tune your eyes to spot his distinctive visage, with its pencil moustache and slicked-back hair - a look he never changed - you'll see him all the time; silent, reproachful, living testament to Hollywood's heartlessness.
After The Cocoanuts he made over three hundred and fifty films. He received screen credit in maybe three or four.
One where he didn't was Monkey Business (1931). What must it have felt like for him on that set? A major supporting actor in the first Marx Brothers movie and then, just two years later, a nobody in their third.
Poor Cyril Ring. You'll always be a star to me.
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