Shermy's developed a fair amount since the early strips. Here's a strip with him from March 28, 1951, just two years before:
Of course Violet's changed a lot too, but we so rarely see Shermy.
The very earliest strips, to me, look like the kind of thing that might be drawn for a magazine periodical like the
New Yorker, which fits Schulz's early sale to the
Saturday Evening Post. The characters as we see them in today's strip up above are actually
less stylized, they have proportions closer to the human norm, but they're also more obviously something of Schulz's own devising.