Well it wasn't the Classic Moth when One-Design and Offshore Yachtsman published their yearly dinghy review in 1964. These were the International Moths, plain and simple. (Well, the Aussies were doing their own 11-foot thing as well.). The OD-OY blurb shows a picture of a Cates design to leeward of a Ventnor/Dorr Willey type.
Update: George A., Classic Moth historian has posted a comment that the two sailors in the following thumbnail were Warren Bailey and Lewis Twitchell. If that's the case then the leeward Moth is not a Cates but one of Bailey's Mach designs (later massaged into the Cates/Florida design by boat builder Harry Cates).
Here is a picture of Pat Duane from the same time period, winning a Moth regatta in a Cates Moth. One of the best women dinghy sailors in the 1960's, she would go on to be one of the top three U.S teams (sailing with her husband) in the newly introduced Flying Dutchman two-man (or woman!) Olympic class.