Lawrence, I'm not sure on the exact date but but they're still shown as late as 1934 on the premium brands. Then, the 1938 catalogue specifically mentions "no lacing". So, their elimination appears to have taken place sometimes between 1935 and 1938. Hopefully, Wayne or Tom M can narrow that down further.
FYI, CCM's bargain brands, such as Crescent may never have had them, as I don't recall seeing a catalogued model with them. Certainly, they're not present on these models even as far back as the very late 1920s. I'm assuming the reason for the difference between the premium and bargain brands was an easy cost reduction.
